91379885 has 4 divisors (see below), whose sum is σ = 109655868. Its totient is φ = 73103904.

The previous prime is 91379863. The next prime is 91379921. The reversal of 91379885 is 58897319.

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

It can be written as a sum of positive squares in 2 ways, for example, as 25786084 + 65593801 = 5078^2 + 8099^2 .

It is a cyclic number.

It is not a de Polignac number, because 91379885 - 2¹² = 91375789 is a prime.

It is a super-2 number, since 2×91379885² = 16700566765226450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9137984 + ... + 9137993.

It is an arithmetic number, because the mean of its divisors is an integer number (27413967).

Almost surely, 2^91379885 is an apocalyptic number.

It is an amenable number.

91379885 is a deficient number, since it is larger than the sum of its proper divisors (18275983).

91379885 is a wasteful number, since it uses less digits than its factorization.

91379885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18275982.

The product of its digits is 544320, while the sum is 50.

The square root of 91379885 is about 9559.2826613716. The cubic root of 91379885 is about 450.4191732066.

The spelling of 91379885 in words is "ninety-one million, three hundred seventy-nine thousand, eight hundred eighty-five".