20917253574720 has 448 divisors, whose sum is σ = 77779068825600. Its totient is φ = 5277291264000.

The previous prime is 20917253574689. The next prime is 20917253574757. The reversal of 20917253574720 is 2747535271902.

20917253574720 is a `hidden beast` number, since 2 + 0 + 9 + 1 + 72 + 53 + 57 + 472 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 123199327 + ... + 123368993.

Almost surely, 2^{20917253574720} is an apocalyptic number.

20917253574720 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 20917253574720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38889534412800).

20917253574720 is an abundant number, since it is smaller than the sum of its proper divisors (56861815250880).

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

20917253574720 is a wasteful number, since it uses less digits than its factorization.

20917253574720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170463 (or 170447 counting only the distinct ones).

The product of its (nonzero) digits is 7408800, while the sum is 54.

The spelling of 20917253574720 in words is "twenty trillion, nine hundred seventeen billion, two hundred fifty-three million, five hundred seventy-four thousand, seven hundred twenty".