15720656556 has 48 divisors (see below), whose sum is σ = 40255891200. Its totient is φ = 4735302720.

The previous prime is 15720656537. The next prime is 15720656591. The reversal of 15720656556 is 65565602751.

It is a happy number.

It is a super-2 number, since 2×15720656556² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334531 + ... + 378618.

It is an arithmetic number, because the mean of its divisors is an integer number (838664400).

Almost surely, 2^15720656556 is an apocalyptic number.

It is an amenable number.

15720656556 is an abundant number, since it is smaller than the sum of its proper divisors (24535234644).

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

15720656556 is a wasteful number, since it uses less digits than its factorization.

15720656556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713334 (or 713332 counting only the distinct ones).

The product of its (nonzero) digits is 1890000, while the sum is 48.

It can be divided in two parts, 15720 and 656556, that added together give a palindrome (672276).

The spelling of 15720656556 in words is "fifteen billion, seven hundred twenty million, six hundred fifty-six thousand, five hundred fifty-six".