20512644 has 12 divisors (see below), whose sum is σ = 47862864. Its totient is φ = 6837544.

The previous prime is 20512579. The next prime is 20512663. The reversal of 20512644 is 44621502.

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, 854682 + ... + 854705.

It is an arithmetic number, because the mean of its divisors is an integer number (3988572).

Almost surely, 2^20512644 is an apocalyptic number.

It is an amenable number.

20512644 is an abundant number, since it is smaller than the sum of its proper divisors (27350220).

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

20512644 is a wasteful number, since it uses less digits than its factorization.

20512644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1709394 (or 1709392 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 20512644 is about 4529.0886500487. The cubic root of 20512644 is about 273.7414400693.

The spelling of 20512644 in words is "twenty million, five hundred twelve thousand, six hundred forty-four".