20317231 has 6 divisors (see below), whose sum is σ = 22332296. Its totient is φ = 18470100.

The previous prime is 20317229. The next prime is 20317247. The reversal of 20317231 is 13271302.

It is not a de Polignac number, because 20317231 - 2¹ = 20317229 is a prime.

It is a super-2 number, since 2×20317231² = 825579751014722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20317199 and 20317208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20347231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 83835 + ... + 84076.

Almost surely, 2^20317231 is an apocalyptic number.

20317231 is a deficient number, since it is larger than the sum of its proper divisors (2015065).

20317231 is a wasteful number, since it uses less digits than its factorization.

20317231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167933 (or 167922 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 20317231 is about 4507.4639210980. The cubic root of 20317231 is about 272.8694022172.

Adding to 20317231 its reverse (13271302), we get a palindrome (33588533).

It can be divided in two parts, 203172 and 31, that added together give a triangular number (203203 = T₆₃₇).

The spelling of 20317231 in words is "twenty million, three hundred seventeen thousand, two hundred thirty-one".