20577728 has 28 divisors (see below), whose sum is σ = 41708832. Its totient is φ = 10068480.

The previous prime is 20577721. The next prime is 20577731. The reversal of 20577728 is 82777502.

It is a junction number, because it is equal to n+sod(n) for n = 20577691 and 20577700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20577721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 413 + ... + 6428.

Almost surely, 2^20577728 is an apocalyptic number.

It is an amenable number.

20577728 is an abundant number, since it is smaller than the sum of its proper divisors (21131104).

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

20577728 is an equidigital number, since it uses as much as digits as its factorization.

20577728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6900 (or 6890 counting only the distinct ones).

The product of its (nonzero) digits is 54880, while the sum is 38.

The square root of 20577728 is about 4536.2680696802. The cubic root of 20577728 is about 274.0306499537.

The spelling of 20577728 in words is "twenty million, five hundred seventy-seven thousand, seven hundred twenty-eight".