20397560 has 16 divisors (see below), whose sum is σ = 45894600. Its totient is φ = 8159008.

The previous prime is 20397551. The next prime is 20397571. The reversal of 20397560 is 6579302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 254930 + ... + 255009.

Almost surely, 2^20397560 is an apocalyptic number.

20397560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20397560 is an abundant number, since it is smaller than the sum of its proper divisors (25497040).

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

20397560 is a wasteful number, since it uses less digits than its factorization.

20397560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 509950 (or 509946 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 32.

The square root of 20397560 is about 4516.3657956370. The cubic root of 20397560 is about 273.2285473150.

The spelling of 20397560 in words is "twenty million, three hundred ninety-seven thousand, five hundred sixty".