20725656 has 128 divisors (see below), whose sum is σ = 64204800. Its totient is φ = 5443200.

The previous prime is 20725631. The next prime is 20725667. The reversal of 20725656 is 65652702.

20725656 is a modest number, since divided by 5656 gives 2072 as remainder.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 137181 + ... + 137331.

It is an arithmetic number, because the mean of its divisors is an integer number (501600).

Almost surely, 2^20725656 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 20725656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32102400).

20725656 is an abundant number, since it is smaller than the sum of its proper divisors (43479144).

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

20725656 is a wasteful number, since it uses less digits than its factorization.

20725656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 33.

The square root of 20725656 is about 4552.5439042364. The cubic root of 20725656 is about 274.6857280369.

The spelling of 20725656 in words is "twenty million, seven hundred twenty-five thousand, six hundred fifty-six".