91398864 has 20 divisors (see below), whose sum is σ = 236113856. Its totient is φ = 30466272.

The previous prime is 91398863. The next prime is 91398869. The reversal of 91398864 is 46889319.

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 1904143 = 91398864 / (9 + 1 + 3 + 9 + 8 + 8 + 6 + 4).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91398863) 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, 952024 + ... + 952119.

Almost surely, 2^91398864 is an apocalyptic number.

It is an amenable number.

91398864 is an abundant number, since it is smaller than the sum of its proper divisors (144714992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91398864 is a wasteful number, since it uses less digits than its factorization.

91398864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1904154 (or 1904148 counting only the distinct ones).

The product of its digits is 373248, while the sum is 48.

The square root of 91398864 is about 9560.2753098433. The cubic root of 91398864 is about 450.4503540795.

The spelling of 91398864 in words is "ninety-one million, three hundred ninety-eight thousand, eight hundred sixty-four".