91791166615425 has 18 divisors (see below), whose sum is σ = 164408178427142. Its totient is φ = 48955288861440.

The previous prime is 91791166615403. The next prime is 91791166615427. The reversal of 91791166615425 is 52451666119719.

It can be written as a sum of positive squares in 3 ways, for example, as 1479748169601 + 90311418445824 = 1216449^2 + 9503232^2 .

It is not a de Polignac number, because 91791166615425 - 2⁹ = 91791166614913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91791166615427) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 203980370032 + ... + 203980370481.

Almost surely, 2^{91791166615425} is an apocalyptic number.

It is an amenable number.

91791166615425 is a deficient number, since it is larger than the sum of its proper divisors (72617011811717).

91791166615425 is a wasteful number, since it uses less digits than its factorization.

91791166615425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407960740529 (or 407960740521 counting only the distinct ones).

The product of its digits is 24494400, while the sum is 63.

The spelling of 91791166615425 in words is "ninety-one trillion, seven hundred ninety-one billion, one hundred sixty-six million, six hundred fifteen thousand, four hundred twenty-five".