23021657920 has 28 divisors (see below), whose sum is σ = 54820323684. Its totient is φ = 9208663040.

The previous prime is 23021657909. The next prime is 23021657977. The reversal of 23021657920 is 2975612032.

It can be written as a sum of positive squares in 2 ways, for example, as 15342290496 + 7679367424 = 123864^2 + 87632^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 23021657920.

It is a congruent 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, 35971021 + ... + 35971660.

It is an arithmetic number, because the mean of its divisors is an integer number (1957868703).

Almost surely, 2^23021657920 is an apocalyptic number.

23021657920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23021657920 is an abundant number, since it is smaller than the sum of its proper divisors (31798665764).

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

23021657920 is an equidigital number, since it uses as much as digits as its factorization.

23021657920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71942698 (or 71942688 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 37.

The spelling of 23021657920 in words is "twenty-three billion, twenty-one million, six hundred fifty-seven thousand, nine hundred twenty".