90656820 has 120 divisors (see below), whose sum is σ = 287600544. Its totient is φ = 23903424.

The previous prime is 90656779. The next prime is 90656821. The reversal of 90656820 is 2865609.

90656820 is a `hidden beast` number, since 90 + 6 + 568 + 2 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90656821) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 173079 + ... + 173601.

Almost surely, 2^90656820 is an apocalyptic number.

90656820 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 90656820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143800272).

90656820 is an abundant number, since it is smaller than the sum of its proper divisors (196943724).

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

90656820 is a wasteful number, since it uses less digits than its factorization.

90656820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 651 (or 640 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 90656820 is about 9521.3875039303. The cubic root of 90656820 is about 449.2280097151.

The spelling of 90656820 in words is "ninety million, six hundred fifty-six thousand, eight hundred twenty".