20520928 has 12 divisors (see below), whose sum is σ = 40400640. Its totient is φ = 10260448.

The previous prime is 20520901. The next prime is 20520937. The reversal of 20520928 is 82902502.

It is a super-2 number, since 2×20520928² = 842216971962368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20520896 and 20520905.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320608 + ... + 320671.

It is an arithmetic number, because the mean of its divisors is an integer number (3366720).

Almost surely, 2^20520928 is an apocalyptic number.

It is an amenable number.

20520928 is a deficient number, since it is larger than the sum of its proper divisors (19879712).

20520928 is an equidigital number, since it uses as much as digits as its factorization.

20520928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641289 (or 641281 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 20520928 is about 4530.0030905067. The cubic root of 20520928 is about 273.7782851308.

Subtracting from 20520928 its sum of digits (28), we obtain a square (20520900 = 4530²).

The spelling of 20520928 in words is "twenty million, five hundred twenty thousand, nine hundred twenty-eight".