231997547681 has 2 divisors, whose sum is σ = 231997547682. Its totient is φ = 231997547680.

The previous prime is 231997547609. The next prime is 231997547773. The reversal of 231997547681 is 186745799132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 131609328400 + 100388219281 = 362780^2 + 316841^2 .

It is a cyclic number.

It is not a de Polignac number, because 231997547681 - 2³⁰ = 230923805857 is a prime.

It is a super-2 number, since 2×231997547681² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (231991547681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115998773840 + 115998773841.

It is an arithmetic number, because the mean of its divisors is an integer number (115998773841).

Almost surely, 2^231997547681 is an apocalyptic number.

It is an amenable number.

231997547681 is a deficient number, since it is larger than the sum of its proper divisors (1).

231997547681 is an equidigital number, since it uses as much as digits as its factorization.

231997547681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22861440, while the sum is 62.

The spelling of 231997547681 in words is "two hundred thirty-one billion, nine hundred ninety-seven million, five hundred forty-seven thousand, six hundred eighty-one".