91621908 has 96 divisors (see below), whose sum is σ = 287481600. Its totient is φ = 24634368.

The previous prime is 91621883. The next prime is 91621927. The reversal of 91621908 is 80912619.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9288 + ... + 16416.

It is an arithmetic number, because the mean of its divisors is an integer number (2994600).

Almost surely, 2^91621908 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 91621908, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143740800).

91621908 is an abundant number, since it is smaller than the sum of its proper divisors (195859692).

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

91621908 is a wasteful number, since it uses less digits than its factorization.

91621908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7166 (or 7158 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 91621908 is about 9571.9333470308. The cubic root of 91621908 is about 450.8164732628.

It can be divided in two parts, 91621 and 908, that added together give a palindrome (92529).

The spelling of 91621908 in words is "ninety-one million, six hundred twenty-one thousand, nine hundred eight".