18921111792 has 80 divisors (see below), whose sum is σ = 56459814912. Its totient is φ = 5396392960.

The previous prime is 18921111787. The next prime is 18921111823. The reversal of 18921111792 is 29711112981.

It is a super-2 number, since 2×18921111792² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1045008 + ... + 1062959.

Almost surely, 2^18921111792 is an apocalyptic number.

18921111792 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18921111792 is an abundant number, since it is smaller than the sum of its proper divisors (37538703120).

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

18921111792 is a wasteful number, since it uses less digits than its factorization.

18921111792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2108006 (or 2108000 counting only the distinct ones).

The product of its digits is 18144, while the sum is 42.

The spelling of 18921111792 in words is "eighteen billion, nine hundred twenty-one million, one hundred eleven thousand, seven hundred ninety-two".