16556557056 has 72 divisors (see below), whose sum is σ = 47454198960. Its totient is φ = 5094322176.

The previous prime is 16556557051. The next prime is 16556557063. The reversal of 16556557056 is 65075565561.

It is not an unprimeable number, because it can be changed into a prime (16556557051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 819171 + ... + 839138.

Almost surely, 2^16556557056 is an apocalyptic number.

16556557056 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

16556557056 is an abundant number, since it is smaller than the sum of its proper divisors (30897641904).

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

16556557056 is a wasteful number, since it uses less digits than its factorization.

16556557056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1658341 (or 1658327 counting only the distinct ones).

The product of its (nonzero) digits is 4725000, while the sum is 51.

The spelling of 16556557056 in words is "sixteen billion, five hundred fifty-six million, five hundred fifty-seven thousand, fifty-six".