20664090 has 24 divisors (see below), whose sum is σ = 53726868. Its totient is φ = 5510400.

The previous prime is 20664031. The next prime is 20664113. The reversal of 20664090 is 9046602.

It can be written as a sum of positive squares in 2 ways, for example, as 19793601 + 870489 = 4449^2 + 933^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 114711 + ... + 114890.

Almost surely, 2^20664090 is an apocalyptic number.

20664090 is an abundant number, since it is smaller than the sum of its proper divisors (33062778).

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

20664090 is a wasteful number, since it uses less digits than its factorization.

20664090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229614 (or 229611 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 20664090 is about 4545.7771612784. Note that the first 3 decimals coincide. The cubic root of 20664090 is about 274.4134716871.

The spelling of 20664090 in words is "twenty million, six hundred sixty-four thousand, ninety".