99518391 has 24 divisors (see below), whose sum is σ = 173949984. Its totient is φ = 53521920.

The previous prime is 99518381. The next prime is 99518399. The reversal of 99518391 is 19381599.

It is not a de Polignac number, because 99518391 - 2⁵ = 99518359 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99518399) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 45390 + ... + 47531.

It is an arithmetic number, because the mean of its divisors is an integer number (7247916).

Almost surely, 2^99518391 is an apocalyptic number.

99518391 is a deficient number, since it is larger than the sum of its proper divisors (74431593).

99518391 is a wasteful number, since it uses less digits than its factorization.

99518391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92951 (or 92948 counting only the distinct ones).

The product of its digits is 87480, while the sum is 45.

The square root of 99518391 is about 9975.8904865681. The cubic root of 99518391 is about 463.4125402718.

The spelling of 99518391 in words is "ninety-nine million, five hundred eighteen thousand, three hundred ninety-one".