231340431 has 16 divisors (see below), whose sum is σ = 357350144. Its totient is φ = 130382784.

The previous prime is 231340429. The next prime is 231340477. The reversal of 231340431 is 134043132.

It is not a de Polignac number, because 231340431 - 2¹ = 231340429 is a prime.

It is a super-2 number, since 2×231340431² = 107036790030531522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 231340398 and 231340407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231340931) 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, 73921 + ... + 76986.

It is an arithmetic number, because the mean of its divisors is an integer number (22334384).

Almost surely, 2^231340431 is an apocalyptic number.

231340431 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

231340431 is a deficient number, since it is larger than the sum of its proper divisors (126009713).

231340431 is a wasteful number, since it uses less digits than its factorization.

231340431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150990.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 231340431 is about 15209.8793880819. The cubic root of 231340431 is about 613.8805121742.

Adding to 231340431 its reverse (134043132), we get a palindrome (365383563).

The spelling of 231340431 in words is "two hundred thirty-one million, three hundred forty thousand, four hundred thirty-one".