20620656 has 100 divisors (see below), whose sum is σ = 68238192. Its totient is φ = 5889024.

The previous prime is 20620651. The next prime is 20620667. The reversal of 20620656 is 65602602.

20620656 is a `hidden beast` number, since 2 + 0 + 6 + 2 + 0 + 656 = 666.

It is a super-2 number, since 2×20620656² = 850422907740672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20620651) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7936 + ... + 10208.

Almost surely, 2^20620656 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 20620656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34119096).

20620656 is an abundant number, since it is smaller than the sum of its proper divisors (47617536).

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

20620656 is a wasteful number, since it uses less digits than its factorization.

20620656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2300 (or 2285 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20620656 is about 4540.9972473015. The cubic root of 20620656 is about 274.2210729367.

The spelling of 20620656 in words is "twenty million, six hundred twenty thousand, six hundred fifty-six".