91782513 has 12 divisors (see below), whose sum is σ = 133156660. Its totient is φ = 60919776.

The previous prime is 91782499. The next prime is 91782517. The reversal of 91782513 is 31528719.

It can be written as a sum of positive squares in 2 ways, for example, as 71774784 + 20007729 = 8472^2 + 4473^2 .

It is not a de Polignac number, because 91782513 - 2⁹ = 91782001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91782517) 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, 20206 + ... + 24327.

Almost surely, 2^91782513 is an apocalyptic number.

It is an amenable number.

91782513 is a deficient number, since it is larger than the sum of its proper divisors (41374147).

91782513 is a wasteful number, since it uses less digits than its factorization.

91782513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44768 (or 44765 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 91782513 is about 9580.3190447918. The cubic root of 91782513 is about 451.0797331347.

The spelling of 91782513 in words is "ninety-one million, seven hundred eighty-two thousand, five hundred thirteen".