20897403730560 has 2304 divisors, whose sum is σ = 93003170457600. Its totient is φ = 4225525678080.

The previous prime is 20897403730549. The next prime is 20897403730561. The reversal of 20897403730560 is 6503730479802.

20897403730560 is a `hidden beast` number, since 2 + 0 + 8 + 9 + 7 + 4 + 0 + 3 + 73 + 0 + 560 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 20897403730497 and 20897403730506.

It is not an unprimeable number, because it can be changed into a prime (20897403730561) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 13085411682 + ... + 13085413278.

It is an arithmetic number, because the mean of its divisors is an integer number (40365959400).

Almost surely, 2^{20897403730560} is an apocalyptic number.

20897403730560 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 20897403730560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46501585228800).

20897403730560 is an abundant number, since it is smaller than the sum of its proper divisors (72105766727040).

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

20897403730560 is a wasteful number, since it uses less digits than its factorization.

20897403730560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1727 (or 1693 counting only the distinct ones).

The product of its (nonzero) digits is 7620480, while the sum is 54.

The spelling of 20897403730560 in words is "twenty trillion, eight hundred ninety-seven billion, four hundred three million, seven hundred thirty thousand, five hundred sixty".