20653931 has 16 divisors (see below), whose sum is σ = 22909440. Its totient is φ = 18532800.

The previous prime is 20653921. The next prime is 20653939. The reversal of 20653931 is 13935602.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20653931 is a prime.

It is a super-2 number, since 2×20653931² = 853169731505522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 20653894 and 20653903.

It is not an unprimeable number, because it can be changed into a prime (20653939) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65831 + ... + 66143.

It is an arithmetic number, because the mean of its divisors is an integer number (1431840).

Almost surely, 2^20653931 is an apocalyptic number.

20653931 is a deficient number, since it is larger than the sum of its proper divisors (2255509).

20653931 is a wasteful number, since it uses less digits than its factorization.

20653931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506.

The product of its (nonzero) digits is 4860, while the sum is 29.

The square root of 20653931 is about 4544.6596132164. The cubic root of 20653931 is about 274.3684947339.

The spelling of 20653931 in words is "twenty million, six hundred fifty-three thousand, nine hundred thirty-one".