231521042115551 has 12 divisors (see below), whose sum is σ = 238271464160640. Its totient is φ = 224952869020320.

The previous prime is 231521042115509. The next prime is 231521042115557. The reversal of 231521042115551 is 155511240125132.

It is not a de Polignac number, because 231521042115551 - 2⁶ = 231521042115487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231521042115557) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 327432686 + ... + 328139003.

It is an arithmetic number, because the mean of its divisors is an integer number (19855955346720).

Almost surely, 2^{231521042115551} is an apocalyptic number.

231521042115551 is a deficient number, since it is larger than the sum of its proper divisors (6750422045089).

231521042115551 is an equidigital number, since it uses as much as digits as its factorization.

231521042115551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 655571966 (or 655571923 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 38.

The spelling of 231521042115551 in words is "two hundred thirty-one trillion, five hundred twenty-one billion, forty-two million, one hundred fifteen thousand, five hundred fifty-one".