20556120 has 64 divisors (see below), whose sum is σ = 66417120. Its totient is φ = 5059584.

The previous prime is 20556113. The next prime is 20556121. The reversal of 20556120 is 2165502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20556121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5029 + ... + 8148.

Almost surely, 2^20556120 is an apocalyptic number.

20556120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20556120 is an abundant number, since it is smaller than the sum of its proper divisors (45861000).

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

20556120 is a wasteful number, since it uses less digits than its factorization.

20556120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13204 (or 13200 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 20556120 is about 4533.8857506558. The cubic root of 20556120 is about 273.9346994829.

The spelling of 20556120 in words is "twenty million, five hundred fifty-six thousand, one hundred twenty".