99891215 has 16 divisors (see below), whose sum is σ = 123420672. Its totient is φ = 77573664.

The previous prime is 99891191. The next prime is 99891251. The reversal of 99891215 is 51219899.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 99891215 - 2¹² = 99887119 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 28172 + ... + 31518.

It is an arithmetic number, because the mean of its divisors is an integer number (7713792).

Almost surely, 2^99891215 is an apocalyptic number.

99891215 is a deficient number, since it is larger than the sum of its proper divisors (23529457).

99891215 is a wasteful number, since it uses less digits than its factorization.

99891215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3526.

The product of its digits is 58320, while the sum is 44.

The square root of 99891215 is about 9994.5592699228. The cubic root of 99891215 is about 463.9905105446.

The spelling of 99891215 in words is "ninety-nine million, eight hundred ninety-one thousand, two hundred fifteen".