91015998 has 16 divisors (see below), whose sum is σ = 182157456. Its totient is φ = 30317760.

The previous prime is 91015987. The next prime is 91016027. The reversal of 91015998 is 89951019.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6090 + ... + 14802.

It is an arithmetic number, because the mean of its divisors is an integer number (11384841).

Almost surely, 2^91015998 is an apocalyptic number.

91015998 is an abundant number, since it is smaller than the sum of its proper divisors (91141458).

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

91015998 is a wasteful number, since it uses less digits than its factorization.

91015998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10459.

The product of its (nonzero) digits is 29160, while the sum is 42.

The square root of 91015998 is about 9540.2305003600. The cubic root of 91015998 is about 449.8205012495.

The spelling of 91015998 in words is "ninety-one million, fifteen thousand, nine hundred ninety-eight".