20457564 has 24 divisors (see below), whose sum is σ = 47807760. Its totient is φ = 6808704.

The previous prime is 20457533. The next prime is 20457583. The reversal of 20457564 is 46575402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13602 + ... + 15030.

It is an arithmetic number, because the mean of its divisors is an integer number (1991990).

Almost surely, 2^20457564 is an apocalyptic number.

It is an amenable number.

20457564 is an abundant number, since it is smaller than the sum of its proper divisors (27350196).

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

20457564 is a wasteful number, since it uses less digits than its factorization.

20457564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2629 (or 2627 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 33.

The square root of 20457564 is about 4523.0038691118. The cubic root of 20457564 is about 273.4962060553.

The spelling of 20457564 in words is "twenty million, four hundred fifty-seven thousand, five hundred sixty-four".