16556390544 has 40 divisors (see below), whose sum is σ = 45021766240. Its totient is φ = 5228333568.

The previous prime is 16556390509. The next prime is 16556390573. The reversal of 16556390544 is 44509365561.

It is a super-2 number, since 2×16556390544² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 16556390493 and 16556390502.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9076057 + ... + 9077880.

It is an arithmetic number, because the mean of its divisors is an integer number (1125544156).

Almost surely, 2^16556390544 is an apocalyptic number.

It is an amenable number.

16556390544 is an abundant number, since it is smaller than the sum of its proper divisors (28465375696).

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

16556390544 is a wasteful number, since it uses less digits than its factorization.

16556390544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18153967 (or 18153961 counting only the distinct ones).

The product of its (nonzero) digits is 1944000, while the sum is 48.

The spelling of 16556390544 in words is "sixteen billion, five hundred fifty-six million, three hundred ninety thousand, five hundred forty-four".