20564028 has 18 divisors (see below), whose sum is σ = 51981384. Its totient is φ = 6854664.

The previous prime is 20564021. The next prime is 20564039. The reversal of 20564028 is 82046502.

It is a tau number, because it is divible by the number of its divisors (18).

It is a junction number, because it is equal to n+sod(n) for n = 20563992 and 20564010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20564021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 285576 + ... + 285647.

Almost surely, 2^20564028 is an apocalyptic number.

It is an amenable number.

20564028 is an abundant number, since it is smaller than the sum of its proper divisors (31417356).

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

20564028 is a wasteful number, since it uses less digits than its factorization.

20564028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 571233 (or 571228 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 20564028 is about 4534.7577664083. The cubic root of 20564028 is about 273.9698228083.

It can be divided in two parts, 2056 and 4028, that added together give a square (6084 = 78²).

The spelling of 20564028 in words is "twenty million, five hundred sixty-four thousand, twenty-eight".