231173564721 has 16 divisors (see below), whose sum is σ = 337720820160. Its totient is φ = 139493373120.

The previous prime is 231173564683. The next prime is 231173564729. The reversal of 231173564721 is 127465371132.

It is not a de Polignac number, because 231173564721 - 2⁷ = 231173564593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231173564729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15287770 + ... + 15302883.

It is an arithmetic number, because the mean of its divisors is an integer number (21107551260).

Almost surely, 2^231173564721 is an apocalyptic number.

It is an amenable number.

231173564721 is a deficient number, since it is larger than the sum of its proper divisors (106547255439).

231173564721 is a wasteful number, since it uses less digits than its factorization.

231173564721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30590896.

The product of its digits is 211680, while the sum is 42.

The spelling of 231173564721 in words is "two hundred thirty-one billion, one hundred seventy-three million, five hundred sixty-four thousand, seven hundred twenty-one".