15506660555 has 4 divisors (see below), whose sum is σ = 18607992672. Its totient is φ = 12405328440.

The previous prime is 15506660539. The next prime is 15506660579. The reversal of 15506660555 is 55506660551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55506660551 = 103 ⋅538899617.

It is not a de Polignac number, because 15506660555 - 2⁴ = 15506660539 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1550666051 + ... + 1550666060.

It is an arithmetic number, because the mean of its divisors is an integer number (4651998168).

Almost surely, 2^15506660555 is an apocalyptic number.

15506660555 is a deficient number, since it is larger than the sum of its proper divisors (3101332117).

15506660555 is an equidigital number, since it uses as much as digits as its factorization.

15506660555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3101332116.

The product of its (nonzero) digits is 675000, while the sum is 44.

The spelling of 15506660555 in words is "fifteen billion, five hundred six million, six hundred sixty thousand, five hundred fifty-five".