20900520 has 48 divisors (see below), whose sum is σ = 67927860. Its totient is φ = 5573376.

The previous prime is 20900489. The next prime is 20900527. The reversal of 20900520 is 2500902.

It can be written as a sum of positive squares in 2 ways, for example, as 20738916 + 161604 = 4554^2 + 402^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20900493 and 20900502.

It is not an unprimeable number, because it can be changed into a prime (20900527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28669 + ... + 29388.

Almost surely, 2^20900520 is an apocalyptic number.

20900520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20900520 is an abundant number, since it is smaller than the sum of its proper divisors (47027340).

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

20900520 is a wasteful number, since it uses less digits than its factorization.

20900520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58074 (or 58067 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 20900520 is about 4571.7086521343. The cubic root of 20900520 is about 275.4560806490.

The spelling of 20900520 in words is "twenty million, nine hundred thousand, five hundred twenty".