90656640 has 96 divisors (see below), whose sum is σ = 313068600. Its totient is φ = 24173568.

The previous prime is 90656633. The next prime is 90656651. The reversal of 90656640 is 4665609.

It is a happy number.

90656640 is a `hidden beast` number, since 9 + 0 + 6 + 5 + 6 + 640 = 666.

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

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

It is a junction number, because it is equal to n+sod(n) for n = 90656595 and 90656604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2110 + ... + 13629.

Almost surely, 2^90656640 is an apocalyptic number.

90656640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90656640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156534300).

90656640 is an abundant number, since it is smaller than the sum of its proper divisors (222411960).

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

90656640 is a wasteful number, since it uses less digits than its factorization.

90656640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15764 (or 15749 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 90656640 is about 9521.3780515217. The cubic root of 90656640 is about 449.2277123994.

The spelling of 90656640 in words is "ninety million, six hundred fifty-six thousand, six hundred forty".