20565120 has 64 divisors (see below), whose sum is σ = 65557440. Its totient is φ = 5483520.

The previous prime is 20565109. The next prime is 20565133. The reversal of 20565120 is 2156502.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×20565120² = 845848321228800, which contains 22 as substring.

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, 3436 + ... + 7275.

It is an arithmetic number, because the mean of its divisors is an integer number (1024335).

Almost surely, 2^20565120 is an apocalyptic number.

20565120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20565120 is an abundant number, since it is smaller than the sum of its proper divisors (44992320).

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

20565120 is a wasteful number, since it uses less digits than its factorization.

20565120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10733 (or 10721 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 20565120 is about 4534.8781681540. The cubic root of 20565120 is about 273.9746722109.

The spelling of 20565120 in words is "twenty million, five hundred sixty-five thousand, one hundred twenty".