21923904020 has 24 divisors (see below), whose sum is σ = 46045149864. Its totient is φ = 8768618496.

The previous prime is 21923904001. The next prime is 21923904029. The reversal of 21923904020 is 2040932912.

It can be written as a sum of positive squares in 4 ways, for example, as 9301830916 + 12622073104 = 96446^2 + 112348^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21923904029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149684 + ... + 257396.

It is an arithmetic number, because the mean of its divisors is an integer number (1918547911).

Almost surely, 2^21923904020 is an apocalyptic number.

21923904020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21923904020 is an abundant number, since it is smaller than the sum of its proper divisors (24121245844).

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

21923904020 is a wasteful number, since it uses less digits than its factorization.

21923904020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117899 (or 117897 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The spelling of 21923904020 in words is "twenty-one billion, nine hundred twenty-three million, nine hundred four thousand, twenty".