231395137 has 2 divisors, whose sum is σ = 231395138. Its totient is φ = 231395136.

The previous prime is 231395093. The next prime is 231395173. The reversal of 231395137 is 731593132.

It is a happy number.

Together with next prime (231395173) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 227135041 + 4260096 = 15071^2 + 2064^2 .

It is a cyclic number.

It is not a de Polignac number, because 231395137 - 2⁷ = 231395009 is a prime.

It is not a weakly prime, because it can be changed into another prime (231395237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115697568 + 115697569.

It is an arithmetic number, because the mean of its divisors is an integer number (115697569).

Almost surely, 2^231395137 is an apocalyptic number.

It is an amenable number.

231395137 is a deficient number, since it is larger than the sum of its proper divisors (1).

231395137 is an equidigital number, since it uses as much as digits as its factorization.

231395137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17010, while the sum is 34.

The square root of 231395137 is about 15211.6776523827. The cubic root of 231395137 is about 613.9288972898.

The spelling of 231395137 in words is "two hundred thirty-one million, three hundred ninety-five thousand, one hundred thirty-seven".