20897560 has 16 divisors (see below), whose sum is σ = 47019600. Its totient is φ = 8359008.

The previous prime is 20897557. The next prime is 20897561. The reversal of 20897560 is 6579802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20897561) 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, 261180 + ... + 261259.

It is an arithmetic number, because the mean of its divisors is an integer number (2938725).

Almost surely, 2^20897560 is an apocalyptic number.

20897560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20897560 is an abundant number, since it is smaller than the sum of its proper divisors (26122040).

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

20897560 is a wasteful number, since it uses less digits than its factorization.

20897560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522450 (or 522446 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 20897560 is about 4571.3849105058. The cubic root of 20897560 is about 275.4430763714.

The spelling of 20897560 in words is "twenty million, eight hundred ninety-seven thousand, five hundred sixty".