231208531 has 2 divisors, whose sum is σ = 231208532. Its totient is φ = 231208530.

The previous prime is 231208507. The next prime is 231208541. The reversal of 231208531 is 135802132.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 231208531 - 2¹³ = 231200339 is a prime.

It is a super-2 number, since 2×231208531² = 106914769614355922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231208496 and 231208505.

It is not a weakly prime, because it can be changed into another prime (231208501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115604265 + 115604266.

It is an arithmetic number, because the mean of its divisors is an integer number (115604266).

Almost surely, 2^231208531 is an apocalyptic number.

231208531 is a deficient number, since it is larger than the sum of its proper divisors (1).

231208531 is an equidigital number, since it uses as much as digits as its factorization.

231208531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 231208531 is about 15205.5427722920. The cubic root of 231208531 is about 613.7638208941.

The spelling of 231208531 in words is "two hundred thirty-one million, two hundred eight thousand, five hundred thirty-one".