15601665516 has 12 divisors (see below), whose sum is σ = 36403886232. Its totient is φ = 5200555168.

The previous prime is 15601665511. The next prime is 15601665517. The reversal of 15601665516 is 61556610651.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (15601665511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 650069385 + ... + 650069408.

It is an arithmetic number, because the mean of its divisors is an integer number (3033657186).

Almost surely, 2^15601665516 is an apocalyptic number.

It is an amenable number.

15601665516 is an abundant number, since it is smaller than the sum of its proper divisors (20802220716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15601665516 is a wasteful number, since it uses less digits than its factorization.

15601665516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1300138800 (or 1300138798 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 42.

The spelling of 15601665516 in words is "fifteen billion, six hundred one million, six hundred sixty-five thousand, five hundred sixteen".