91499968 has 56 divisors (see below), whose sum is σ = 208922112. Its totient is φ = 38947584.

The previous prime is 91499951. The next prime is 91499981. The reversal of 91499968 is 86999419.

It is a tau number, because it is divible by the number of its divisors (56).

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, 74205 + ... + 75427.

It is an arithmetic number, because the mean of its divisors is an integer number (3730752).

Almost surely, 2^91499968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91499968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104461056).

91499968 is an abundant number, since it is smaller than the sum of its proper divisors (117422144).

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

91499968 is a wasteful number, since it uses less digits than its factorization.

91499968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1409 (or 1399 counting only the distinct ones).

The product of its digits is 1259712, while the sum is 55.

The square root of 91499968 is about 9565.5615621876. The cubic root of 91499968 is about 450.6163865959.

The spelling of 91499968 in words is "ninety-one million, four hundred ninety-nine thousand, nine hundred sixty-eight".