91791579 has 16 divisors (see below), whose sum is σ = 136773504. Its totient is φ = 54273600.

The previous prime is 91791577. The next prime is 91791593. The reversal of 91791579 is 97519719.

It is a happy number.

It is not a de Polignac number, because 91791579 - 2¹ = 91791577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91791577) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32569 + ... + 35274.

It is an arithmetic number, because the mean of its divisors is an integer number (8548344).

Almost surely, 2^91791579 is an apocalyptic number.

91791579 is a deficient number, since it is larger than the sum of its proper divisors (44981925).

91791579 is a wasteful number, since it uses less digits than its factorization.

91791579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67898.

The product of its digits is 178605, while the sum is 48.

The square root of 91791579 is about 9580.7921906281. The cubic root of 91791579 is about 451.0945847445.

The spelling of 91791579 in words is "ninety-one million, seven hundred ninety-one thousand, five hundred seventy-nine".