20440656 has 120 divisors (see below), whose sum is σ = 62416640. Its totient is φ = 6220800.

The previous prime is 20440649. The next prime is 20440691. The reversal of 20440656 is 65604402.

It is a happy number.

20440656 is a `hidden beast` number, since 2 + 0 + 4 + 4 + 0 + 656 = 666.

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 23 ways as a sum of consecutive naturals, for example, 84696 + ... + 84936.

Almost surely, 2^20440656 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 20440656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31208320).

20440656 is an abundant number, since it is smaller than the sum of its proper divisors (41975984).

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

20440656 is a wasteful number, since it uses less digits than its factorization.

20440656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305 (or 296 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20440656 is about 4521.1343709295. The cubic root of 20440656 is about 273.4208378701.

The spelling of 20440656 in words is "twenty million, four hundred forty thousand, six hundred fifty-six".