20842560 has 84 divisors (see below), whose sum is σ = 71699628. Its totient is φ = 5557248.

The previous prime is 20842553. The next prime is 20842579. The reversal of 20842560 is 6524802.

20842560 is a `hidden beast` number, since 20 + 84 + 2 + 560 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 10653696 + 10188864 = 3264^2 + 3192^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 739 + ... + 6498.

It is an arithmetic number, because the mean of its divisors is an integer number (853567).

Almost surely, 2^20842560 is an apocalyptic number.

20842560 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 20842560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35849814).

20842560 is an abundant number, since it is smaller than the sum of its proper divisors (50857068).

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

20842560 is a wasteful number, since it uses less digits than its factorization.

20842560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7260 (or 7247 counting only the distinct ones).

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

The square root of 20842560 is about 4565.3652646858. The cubic root of 20842560 is about 275.2012191221.

The spelling of 20842560 in words is "twenty million, eight hundred forty-two thousand, five hundred sixty".