20904732 has 18 divisors (see below), whose sum is σ = 52842608. Its totient is φ = 6968232.

The previous prime is 20904701. The next prime is 20904733. The reversal of 20904732 is 23740902.

It is a tau number, because it is divible by the number of its divisors (18).

It is a junction number, because it is equal to n+sod(n) for n = 20904696 and 20904705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20904733) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 290308 + ... + 290379.

Almost surely, 2^20904732 is an apocalyptic number.

It is an amenable number.

20904732 is an abundant number, since it is smaller than the sum of its proper divisors (31937876).

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

20904732 is a wasteful number, since it uses less digits than its factorization.

20904732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580697 (or 580692 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 20904732 is about 4572.1692882045. The cubic root of 20904732 is about 275.4745832681.

The spelling of 20904732 in words is "twenty million, nine hundred four thousand, seven hundred thirty-two".