20928560 has 40 divisors (see below), whose sum is σ = 49054896. Its totient is φ = 8303360.

The previous prime is 20928541. The next prime is 20928629. The reversal of 20928560 is 6582902.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9482 + ... + 11478.

Almost surely, 2^20928560 is an apocalyptic number.

20928560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20928560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24527448).

20928560 is an abundant number, since it is smaller than the sum of its proper divisors (28126336).

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

20928560 is a wasteful number, since it uses less digits than its factorization.

20928560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2141 (or 2135 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 20928560 is about 4574.7743113732. The cubic root of 20928560 is about 275.5792089573.

The spelling of 20928560 in words is "twenty million, nine hundred twenty-eight thousand, five hundred sixty".