21492111172 has 12 divisors (see below), whose sum is σ = 42984222400. Its totient is φ = 9210904776.

The previous prime is 21492111169. The next prime is 21492111187. The reversal of 21492111172 is 27111129412.

21492111172 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 383787672 + ... + 383787727.

Almost surely, 2^21492111172 is an apocalyptic number.

It is an amenable number.

21492111172 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.

21492111172 is a wasteful number, since it uses less digits than its factorization.

21492111172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767575410 (or 767575408 counting only the distinct ones).

The product of its digits is 2016, while the sum is 31.

The spelling of 21492111172 in words is "twenty-one billion, four hundred ninety-two million, one hundred eleven thousand, one hundred seventy-two".