20731311 has 12 divisors (see below), whose sum is σ = 29985280. Its totient is φ = 13802400.

The previous prime is 20731309. The next prime is 20731327. The reversal of 20731311 is 11313702.

It is not a de Polignac number, because 20731311 - 2¹ = 20731309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731301) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10611 + ... + 12411.

Almost surely, 2^20731311 is an apocalyptic number.

20731311 is a deficient number, since it is larger than the sum of its proper divisors (9253969).

20731311 is a wasteful number, since it uses less digits than its factorization.

20731311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3086 (or 3083 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 18.

The square root of 20731311 is about 4553.1649432016. The cubic root of 20731311 is about 274.7107084531.

The spelling of 20731311 in words is "twenty million, seven hundred thirty-one thousand, three hundred eleven".