21163188172 has 12 divisors (see below), whose sum is σ = 42326376400. Its totient is φ = 9069937776.

The previous prime is 21163188169. The next prime is 21163188187. The reversal of 21163188172 is 27188136112.

21163188172 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 377914047 + ... + 377914102.

Almost surely, 2^21163188172 is an apocalyptic number.

It is an amenable number.

21163188172 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21163188172 is a wasteful number, since it uses less digits than its factorization.

21163188172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755828160 (or 755828158 counting only the distinct ones).

The product of its digits is 32256, while the sum is 40.

The spelling of 21163188172 in words is "twenty-one billion, one hundred sixty-three million, one hundred eighty-eight thousand, one hundred seventy-two".