91774521 has 6 divisors (see below), whose sum is σ = 132563210. Its totient is φ = 61183008.

The previous prime is 91774499. The next prime is 91774547. The reversal of 91774521 is 12547719.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 84272400 + 7502121 = 9180^2 + 2739^2 .

It is not a de Polignac number, because 91774521 - 2¹⁴ = 91758137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91774591) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5098576 + ... + 5098593.

Almost surely, 2^91774521 is an apocalyptic number.

It is an amenable number.

91774521 is a deficient number, since it is larger than the sum of its proper divisors (40788689).

91774521 is a wasteful number, since it uses less digits than its factorization.

91774521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10197175 (or 10197172 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 91774521 is about 9579.9019306045. The cubic root of 91774521 is about 451.0666401036.

The spelling of 91774521 in words is "ninety-one million, seven hundred seventy-four thousand, five hundred twenty-one".