20927680 has 56 divisors (see below), whose sum is σ = 52779168. Its totient is φ = 7876608.

The previous prime is 20927659. The next prime is 20927689. The reversal of 20927680 is 8672902.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (20927689) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3517 + ... + 7363.

Almost surely, 2^20927680 is an apocalyptic number.

20927680 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 20927680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26389584).

20927680 is an abundant number, since it is smaller than the sum of its proper divisors (31851488).

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

20927680 is a wasteful number, since it uses less digits than its factorization.

20927680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3881 (or 3871 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 20927680 is about 4574.6781307541. The cubic root of 20927680 is about 275.5753464030.

Adding to 20927680 its product of nonzero digits (12096), we get a square (20939776 = 4576²).

It can be divided in two parts, 209 and 27680, that added together give a square (27889 = 167²).

The spelling of 20927680 in words is "twenty million, nine hundred twenty-seven thousand, six hundred eighty".