20928690 has 48 divisors (see below), whose sum is σ = 57283200. Its totient is φ = 5286816.

The previous prime is 20928679. The next prime is 20928703. The reversal of 20928690 is 9682902.

It is a super-2 number, since 2×20928690² = 876020130232200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4410 + ... + 7829.

It is an arithmetic number, because the mean of its divisors is an integer number (1193400).

Almost surely, 2^20928690 is an apocalyptic number.

20928690 is an abundant number, since it is smaller than the sum of its proper divisors (36354510).

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

20928690 is a wasteful number, since it uses less digits than its factorization.

20928690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12271 (or 12268 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 20928690 is about 4574.7885197023. The cubic root of 20928690 is about 275.5797795528.

The spelling of 20928690 in words is "twenty million, nine hundred twenty-eight thousand, six hundred ninety".