20556525 has 24 divisors (see below), whose sum is σ = 37077984. Its totient is φ = 9966400.

The previous prime is 20556521. The next prime is 20556533. The reversal of 20556525 is 52565502.

20556525 = T₃₁₀ + T₃₁₁ + ... + T₅₃₄.

It is not a de Polignac number, because 20556525 - 2² = 20556521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20556492 and 20556501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20556521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11634 + ... + 13283.

It is an arithmetic number, because the mean of its divisors is an integer number (1544916).

Almost surely, 2^20556525 is an apocalyptic number.

20556525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20556525 is a deficient number, since it is larger than the sum of its proper divisors (16521459).

20556525 is a wasteful number, since it uses less digits than its factorization.

20556525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24941 (or 24936 counting only the distinct ones).

The product of its (nonzero) digits is 15000, while the sum is 30.

The square root of 20556525 is about 4533.9304141109. The cubic root of 20556525 is about 273.9364985064.

The spelling of 20556525 in words is "twenty million, five hundred fifty-six thousand, five hundred twenty-five".