91422240 has 432 divisors, whose sum is σ = 378520128. Its totient is φ = 18450432.

The previous prime is 91422229. The next prime is 91422241. The reversal of 91422240 is 4222419.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 91422240.

It is not an unprimeable number, because it can be changed into a prime (91422241) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3974869 + ... + 3974891.

It is an arithmetic number, because the mean of its divisors is an integer number (876204).

Almost surely, 2^91422240 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 91422240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (189260064).

91422240 is an abundant number, since it is smaller than the sum of its proper divisors (287097888).

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

91422240 is a wasteful number, since it uses less digits than its factorization.

91422240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 91422240 is about 9561.4977906184. The cubic root of 91422240 is about 450.4887529153.

Adding to 91422240 its reverse (4222419), we get a palindrome (95644659).

The spelling of 91422240 in words is "ninety-one million, four hundred twenty-two thousand, two hundred forty".