91292640 has 96 divisors (see below), whose sum is σ = 290939040. Its totient is φ = 24059904.

The previous prime is 91292639. The next prime is 91292651. The reversal of 91292640 is 4629219.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×91292640² = 16668692236339200, which contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 41652 + ... + 43788.

It is an arithmetic number, because the mean of its divisors is an integer number (3030615).

Almost surely, 2^91292640 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 91292640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145469520).

91292640 is an abundant number, since it is smaller than the sum of its proper divisors (199646400).

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

91292640 is a wasteful number, since it uses less digits than its factorization.

91292640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2244 (or 2236 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 91292640 is about 9554.7182062058. The cubic root of 91292640 is about 450.2757815706.

The spelling of 91292640 in words is "ninety-one million, two hundred ninety-two thousand, six hundred forty".