20731117 has 16 divisors (see below), whose sum is σ = 23728320. Its totient is φ = 17942400.

The previous prime is 20731097. The next prime is 20731121. The reversal of 20731117 is 71113702.

It is a cyclic number.

It is not a de Polignac number, because 20731117 - 2²³ = 12342509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731127) 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, 18859 + ... + 19927.

It is an arithmetic number, because the mean of its divisors is an integer number (1483020).

Almost surely, 2^20731117 is an apocalyptic number.

It is an amenable number.

20731117 is a deficient number, since it is larger than the sum of its proper divisors (2997203).

20731117 is a wasteful number, since it uses less digits than its factorization.

20731117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1164.

The product of its (nonzero) digits is 294, while the sum is 22.

The square root of 20731117 is about 4553.1436392892. The cubic root of 20731117 is about 274.7098515521.

Adding to 20731117 its reverse (71113702), we get a palindrome (91844819).

It can be divided in two parts, 20 and 731117, that added together give a palindrome (731137).

The spelling of 20731117 in words is "twenty million, seven hundred thirty-one thousand, one hundred seventeen".