Fordyce spots: These are small, yellowish or white bumps on the genitals, including the scrotum, that are caused by the abnormal presence of sebaceous glands in the skin. They are benign and very common, making them the most likely diagnosis for pearly papules on the scrotum.

Angiokeratomas: These are small, dark red to purple spots that can appear on the scrotum and are caused by a dilation of blood vessels. They can sometimes appear pearly due to the overlying skin changes.
Seborrheic keratoses: While more common on other parts of the body, these benign growths can occasionally appear on the scrotum and may have a pearly appearance.
Molluscum contagiosum: A viral infection that causes small, pearly, or flesh-colored bumps. It's contagious and can appear anywhere on the body, including the genital area.

Penile or scrotal cancer: Although rare, any new or changing lesions on the genitals should prompt consideration of malignancy. Certain types of cancer, like squamous cell carcinoma or basal cell carcinoma, could initially present as pearly papules.
Syphilis (secondary stage): This sexually transmitted infection can cause a wide range of skin manifestations, including papules that might appear pearly. Given the potential for serious complications if left untreated, syphilis should always be considered in the differential diagnosis of genital lesions.

Lichen nitidus: A rare skin condition characterized by tiny, shiny, flat-topped bumps that can appear on the genitals among other areas. It's usually benign and self-limiting.
Neurofibromas: Part of neurofibromatosis type 1, these are rare, benign tumors of the nerve tissue that can appear as soft, fleshy growths on the skin, including the scrotum, though they are not typically described as pearly papules.
Eccrine poroma: A rare, benign tumor of the sweat glands that can appear on the skin, including the genital area, and might be described as a pearly papule, though this is uncommon.