21550156100 has 36 divisors (see below), whose sum is σ = 51015099408. Its totient is φ = 7836420000.

The previous prime is 21550156081. The next prime is 21550156127. The reversal of 21550156100 is 165105512.

It is a self number, because there is not a number n which added to its sum of digits gives 21550156100.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9794426 + ... + 9796625.

Almost surely, 2^21550156100 is an apocalyptic number.

21550156100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21550156100 is an abundant number, since it is smaller than the sum of its proper divisors (29464943308).

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

21550156100 is a wasteful number, since it uses less digits than its factorization.

21550156100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19591076 (or 19591069 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 26.

The spelling of 21550156100 in words is "twenty-one billion, five hundred fifty million, one hundred fifty-six thousand, one hundred".