231520521155425 has 6 divisors (see below), whose sum is σ = 287085446232758. Its totient is φ = 185216416924320.

The previous prime is 231520521155401. The next prime is 231520521155513. The reversal of 231520521155425 is 524551125025132.

It can be written as a sum of positive squares in 3 ways, for example, as 36346278609 + 231484174876816 = 190647^2 + 15214604^2 .

It is not a de Polignac number, because 231520521155425 - 2¹¹ = 231520521153377 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4630410423084 + ... + 4630410423133.

Almost surely, 2^{231520521155425} is an apocalyptic number.

231520521155425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

231520521155425 is a deficient number, since it is larger than the sum of its proper divisors (55564925077333).

231520521155425 is an equidigital number, since it uses as much as digits as its factorization.

231520521155425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9260820846227 (or 9260820846222 counting only the distinct ones).

The product of its (nonzero) digits is 600000, while the sum is 43.

The spelling of 231520521155425 in words is "two hundred thirty-one trillion, five hundred twenty billion, five hundred twenty-one million, one hundred fifty-five thousand, four hundred twenty-five".