16621611656 has 32 divisors (see below), whose sum is σ = 33569386200. Its totient is φ = 7670023680.

The previous prime is 16621611647. The next prime is 16621611679. The reversal of 16621611656 is 65611612661.

It can be written as a sum of positive squares in 4 ways, for example, as 16514820100 + 106791556 = 128510^2 + 10334^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 665930 + ... + 690438.

Almost surely, 2^16621611656 is an apocalyptic number.

It is an amenable number.

16621611656 is an abundant number, since it is smaller than the sum of its proper divisors (16947774544).

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

16621611656 is a wasteful number, since it uses less digits than its factorization.

16621611656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31049 (or 31045 counting only the distinct ones).

The product of its digits is 77760, while the sum is 41.

The spelling of 16621611656 in words is "sixteen billion, six hundred twenty-one million, six hundred eleven thousand, six hundred fifty-six".