91038979 has 4 divisors (see below), whose sum is σ = 91080976. Its totient is φ = 90996984.

The previous prime is 91038973. The next prime is 91038989. The reversal of 91038979 is 97983019.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 91038979 - 2¹¹ = 91036931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91038973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17559 + ... + 22144.

It is an arithmetic number, because the mean of its divisors is an integer number (22770244).

Almost surely, 2^91038979 is an apocalyptic number.

91038979 is a deficient number, since it is larger than the sum of its proper divisors (41997).

91038979 is a wasteful number, since it uses less digits than its factorization.

91038979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41996.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 91038979 is about 9541.4348501680. The cubic root of 91038979 is about 449.8583570669.

The spelling of 91038979 in words is "ninety-one million, thirty-eight thousand, nine hundred seventy-nine".