20663659897920 has 2688 divisors, whose sum is σ = 87656754124800. Its totient is φ = 4605103964160.

The previous prime is 20663659897919. The next prime is 20663659897927. The reversal of 20663659897920 is 2979895636602.

20663659897920 is a `hidden beast` number, since 2 + 0 + 6 + 6 + 3 + 6 + 598 + 9 + 7 + 9 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (20663659897927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 76249667385 + ... + 76249667655.

It is an arithmetic number, because the mean of its divisors is an integer number (32610399600).

Almost surely, 2^{20663659897920} is an apocalyptic number.

20663659897920 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 20663659897920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43828377062400).

20663659897920 is an abundant number, since it is smaller than the sum of its proper divisors (66993094226880).

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

20663659897920 is a wasteful number, since it uses less digits than its factorization.

20663659897920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 529079040, while the sum is 72.

The spelling of 20663659897920 in words is "twenty trillion, six hundred sixty-three billion, six hundred fifty-nine million, eight hundred ninety-seven thousand, nine hundred twenty".