20814564 has 12 divisors (see below), whose sum is σ = 48567344. Its totient is φ = 6938184.

The previous prime is 20814559. The next prime is 20814581. The reversal of 20814564 is 46541802.

It is a tau number, because it is divible by the number of its divisors (12).

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, 867262 + ... + 867285.

Almost surely, 2^20814564 is an apocalyptic number.

It is an amenable number.

20814564 is an abundant number, since it is smaller than the sum of its proper divisors (27752780).

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

20814564 is a wasteful number, since it uses less digits than its factorization.

20814564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1734554 (or 1734552 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 20814564 is about 4562.2981051220. The cubic root of 20814564 is about 275.0779459490.

The spelling of 20814564 in words is "twenty million, eight hundred fourteen thousand, five hundred sixty-four".