90311640 has 64 divisors (see below), whose sum is σ = 271641600. Its totient is φ = 24020352.

The previous prime is 90311621. The next prime is 90311651. The reversal of 90311640 is 4611309.

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 90311640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62041 + ... + 63479.

It is an arithmetic number, because the mean of its divisors is an integer number (4244400).

Almost surely, 2^90311640 is an apocalyptic number.

It is an amenable number.

90311640 is an abundant number, since it is smaller than the sum of its proper divisors (181329960).

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

90311640 is a wasteful number, since it uses less digits than its factorization.

90311640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1976 (or 1972 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 90311640 is about 9503.2436567732. The cubic root of 90311640 is about 448.6571324704.

Adding to 90311640 its reverse (4611309), we get a palindrome (94922949).

It can be divided in two parts, 90311 and 640, that added together give a triangular number (90951 = T₄₂₆).

The spelling of 90311640 in words is "ninety million, three hundred eleven thousand, six hundred forty".