91870839 has 12 divisors (see below), whose sum is σ = 140508576. Its totient is φ = 57644352.

The previous prime is 91870817. The next prime is 91870841. The reversal of 91870839 is 93807819.

It is not a de Polignac number, because 91870839 - 2⁹ = 91870327 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91870794 and 91870803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91870859) 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, 300079 + ... + 300384.

It is an arithmetic number, because the mean of its divisors is an integer number (11709048).

Almost surely, 2^91870839 is an apocalyptic number.

91870839 is a deficient number, since it is larger than the sum of its proper divisors (48637737).

91870839 is a wasteful number, since it uses less digits than its factorization.

91870839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600486 (or 600483 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 91870839 is about 9584.9276992578. The cubic root of 91870839 is about 451.2243841271.

The spelling of 91870839 in words is "ninety-one million, eight hundred seventy thousand, eight hundred thirty-nine".