91245680761 has 9 divisors (see below), whose sum is σ = 93242892549. Its totient is φ = 89290388124.

The previous prime is 91245680741. The next prime is 91245680783. The reversal of 91245680761 is 16708654219.

It is a happy number.

The square root of 91245680761 is 302069.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 91245680761 - 2¹⁵ = 91245647993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91245680741) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14194030 + ... + 14200456.

Almost surely, 2^91245680761 is an apocalyptic number.

91245680761 is the 302069-th square number.

91245680761 is the 151035-th centered octagonal number.

It is an amenable number.

91245680761 is a deficient number, since it is larger than the sum of its proper divisors (1997211788).

91245680761 is an frugal number, since it uses more digits than its factorization.

91245680761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12948 (or 6474 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 49.

Multiplying 91245680761 by its sum of digits (49), we get a square (4471038357289 = 2114483²).

The spelling of 91245680761 in words is "ninety-one billion, two hundred forty-five million, six hundred eighty thousand, seven hundred sixty-one".