91663776 has 72 divisors (see below), whose sum is σ = 269103744. Its totient is φ = 29566080.

The previous prime is 91663721. The next prime is 91663777. The reversal of 91663776 is 67736619.

91663776 is a `hidden beast` number, since 9 + 1 + 6 + 637 + 7 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (91663777) 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, 3795 + ... + 14061.

It is an arithmetic number, because the mean of its divisors is an integer number (3737552).

Almost surely, 2^91663776 is an apocalyptic number.

91663776 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91663776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134551872).

91663776 is an abundant number, since it is smaller than the sum of its proper divisors (177439968).

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

91663776 is a wasteful number, since it uses less digits than its factorization.

91663776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10314 (or 10303 counting only the distinct ones).

The product of its digits is 285768, while the sum is 45.

The square root of 91663776 is about 9574.1201162300. The cubic root of 91663776 is about 450.8851319137.

The spelling of 91663776 in words is "ninety-one million, six hundred sixty-three thousand, seven hundred seventy-six".