231156137 has 2 divisors, whose sum is σ = 231156138. Its totient is φ = 231156136.

The previous prime is 231156113. The next prime is 231156139. The reversal of 231156137 is 731651132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 132273001 + 98883136 = 11501^2 + 9944^2 .

It is a cyclic number.

It is not a de Polignac number, because 231156137 - 2¹² = 231152041 is a prime.

Together with 231156139, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (231156139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115578068 + 115578069.

It is an arithmetic number, because the mean of its divisors is an integer number (115578069).

Almost surely, 2^231156137 is an apocalyptic number.

It is an amenable number.

231156137 is a deficient number, since it is larger than the sum of its proper divisors (1).

231156137 is an equidigital number, since it uses as much as digits as its factorization.

231156137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 29.

The square root of 231156137 is about 15203.8198160857. The cubic root of 231156137 is about 613.7174558647.

The spelling of 231156137 in words is "two hundred thirty-one million, one hundred fifty-six thousand, one hundred thirty-seven".