131231237 has 2 divisors, whose sum is σ = 131231238. Its totient is φ = 131231236.

The previous prime is 131231213. The next prime is 131231257. The reversal of 131231237 is 732132131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 112169281 + 19061956 = 10591^2 + 4366^2 .

It is a cyclic number.

It is not a de Polignac number, because 131231237 - 2¹⁸ = 130969093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131231207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65615618 + 65615619.

It is an arithmetic number, because the mean of its divisors is an integer number (65615619).

Almost surely, 2^131231237 is an apocalyptic number.

It is an amenable number.

131231237 is a deficient number, since it is larger than the sum of its proper divisors (1).

131231237 is an equidigital number, since it uses as much as digits as its factorization.

131231237 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 23.

The square root of 131231237 is about 11455.6203236665. The cubic root of 131231237 is about 508.1739605615.

Adding to 131231237 its reverse (732132131), we get a palindrome (863363368).

The spelling of 131231237 in words is "one hundred thirty-one million, two hundred thirty-one thousand, two hundred thirty-seven".