231541215500521 has 2 divisors, whose sum is σ = 231541215500522. Its totient is φ = 231541215500520.

The previous prime is 231541215500509. The next prime is 231541215500657. The reversal of 231541215500521 is 125005512145132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 189933490836496 + 41607724664025 = 13781636^2 + 6450405^2 .

It is a cyclic number.

It is not a de Polignac number, because 231541215500521 - 2⁹ = 231541215500009 is a prime.

It is a super-2 number, since 2×231541215500521² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (231541215507521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115770607750260 + 115770607750261.

It is an arithmetic number, because the mean of its divisors is an integer number (115770607750261).

Almost surely, 2^{231541215500521} is an apocalyptic number.

It is an amenable number.

231541215500521 is a deficient number, since it is larger than the sum of its proper divisors (1).

231541215500521 is an equidigital number, since it uses as much as digits as its factorization.

231541215500521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60000, while the sum is 37.

Adding to 231541215500521 its reverse (125005512145132), we get a palindrome (356546727645653).

The spelling of 231541215500521 in words is "two hundred thirty-one trillion, five hundred forty-one billion, two hundred fifteen million, five hundred thousand, five hundred twenty-one".