20722856 has 32 divisors (see below), whose sum is σ = 48444480. Its totient is φ = 8073600.

The previous prime is 20722853. The next prime is 20722873. The reversal of 20722856 is 65822702.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20722853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16205 + ... + 17436.

It is an arithmetic number, because the mean of its divisors is an integer number (1513890).

Almost surely, 2^20722856 is an apocalyptic number.

It is an amenable number.

20722856 is an abundant number, since it is smaller than the sum of its proper divisors (27721624).

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

20722856 is a wasteful number, since it uses less digits than its factorization.

20722856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33665 (or 33661 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 20722856 is about 4552.2363734762. The cubic root of 20722856 is about 274.6733576255.

The spelling of 20722856 in words is "twenty million, seven hundred twenty-two thousand, eight hundred fifty-six".