20879565 has 32 divisors (see below), whose sum is σ = 39502080. Its totient is φ = 9214464.

The previous prime is 20879531. The next prime is 20879567. The reversal of 20879565 is 56597802.

It is not a de Polignac number, because 20879565 - 2⁶ = 20879501 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20879567) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 384 + ... + 6473.

It is an arithmetic number, because the mean of its divisors is an integer number (1234440).

Almost surely, 2^20879565 is an apocalyptic number.

It is an amenable number.

20879565 is a deficient number, since it is larger than the sum of its proper divisors (18622515).

20879565 is a wasteful number, since it uses less digits than its factorization.

20879565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6901.

The product of its (nonzero) digits is 151200, while the sum is 42.

The square root of 20879565 is about 4569.4162646885. The cubic root of 20879565 is about 275.3639918346.

The spelling of 20879565 in words is "twenty million, eight hundred seventy-nine thousand, five hundred sixty-five".