90032640 has 160 divisors (see below), whose sum is σ = 303462720. Its totient is φ = 22708224.

The previous prime is 90032639. The next prime is 90032653. The reversal of 90032640 is 4623009.

It is a tau number, because it is divible by the number of its divisors (160).

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 90032640.

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, 145612 + ... + 146228.

It is an arithmetic number, because the mean of its divisors is an integer number (1896642).

Almost surely, 2^90032640 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 90032640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151731360).

90032640 is an abundant number, since it is smaller than the sum of its proper divisors (213430080).

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

90032640 is a wasteful number, since it uses less digits than its factorization.

90032640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662 (or 646 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 90032640 is about 9488.5531036086. The cubic root of 90032640 is about 448.1946433119.

Adding to 90032640 its reverse (4623009), we get a palindrome (94655649).

The spelling of 90032640 in words is "ninety million, thirty-two thousand, six hundred forty".