16551621256 has 32 divisors (see below), whose sum is σ = 31349597760. Its totient is φ = 8191801152.

The previous prime is 16551621253. The next prime is 16551621257. The reversal of 16551621256 is 65212615561.

16551621256 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (40) 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 (16551621253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3502111 + ... + 3506833.

It is an arithmetic number, because the mean of its divisors is an integer number (979674930).

Almost surely, 2^16551621256 is an apocalyptic number.

It is an amenable number.

16551621256 is a deficient number, since it is larger than the sum of its proper divisors (14797976504).

16551621256 is a wasteful number, since it uses less digits than its factorization.

16551621256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9085 (or 9081 counting only the distinct ones).

The product of its digits is 108000, while the sum is 40.

The spelling of 16551621256 in words is "sixteen billion, five hundred fifty-one million, six hundred twenty-one thousand, two hundred fifty-six".