20731365 has 12 divisors (see below), whose sum is σ = 35934444. Its totient is φ = 11056704.

The previous prime is 20731351. The next prime is 20731391. The reversal of 20731365 is 56313702.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 15000129 + 5731236 = 3873^2 + 2394^2 .

It is not a de Polignac number, because 20731365 - 2⁶ = 20731301 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 230304 + ... + 230393.

It is an arithmetic number, because the mean of its divisors is an integer number (2994537).

Almost surely, 2^20731365 is an apocalyptic number.

It is an amenable number.

20731365 is a deficient number, since it is larger than the sum of its proper divisors (15203079).

20731365 is a wasteful number, since it uses less digits than its factorization.

20731365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460708 (or 460705 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 27.

The square root of 20731365 is about 4553.1708731389. The cubic root of 20731365 is about 274.7109469710.

The spelling of 20731365 in words is "twenty million, seven hundred thirty-one thousand, three hundred sixty-five".