231997547609 has 2 divisors, whose sum is σ = 231997547610. Its totient is φ = 231997547608.

The previous prime is 231997547591. The next prime is 231997547681. The reversal of 231997547609 is 906745799132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 231904849225 + 92698384 = 481565^2 + 9628^2 .

It is a cyclic number.

It is not a de Polignac number, because 231997547609 - 2³⁶ = 163278070873 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (231997540609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115998773804 + 115998773805.

It is an arithmetic number, because the mean of its divisors is an integer number (115998773805).

Almost surely, 2^231997547609 is an apocalyptic number.

It is an amenable number.

231997547609 is a deficient number, since it is larger than the sum of its proper divisors (1).

231997547609 is an equidigital number, since it uses as much as digits as its factorization.

231997547609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25719120, while the sum is 62.

The spelling of 231997547609 in words is "two hundred thirty-one billion, nine hundred ninety-seven million, five hundred forty-seven thousand, six hundred nine".