20217980795904 has 440 divisors, whose sum is σ = 63622983205760. Its totient is φ = 6377542262784.

The previous prime is 20217980795851. The next prime is 20217980795921. The reversal of 20217980795904 is 40959708971202.

20217980795904 is a `hidden beast` number, since 20 + 2 + 17 + 9 + 8 + 0 + 7 + 9 + 590 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

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 39 ways as a sum of consecutive naturals, for example, 1523923479 + ... + 1523936745.

It is an arithmetic number, because the mean of its divisors is an integer number (144597689104).

Almost surely, 2^{20217980795904} is an apocalyptic number.

20217980795904 is a gapful number since it is divisible by the number (24) 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 20217980795904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31811491602880).

20217980795904 is an abundant number, since it is smaller than the sum of its proper divisors (43405002409856).

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

20217980795904 is a wasteful number, since it uses less digits than its factorization.

20217980795904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14285 (or 14258 counting only the distinct ones).

The product of its (nonzero) digits is 22861440, while the sum is 63.

The spelling of 20217980795904 in words is "twenty trillion, two hundred seventeen billion, nine hundred eighty million, seven hundred ninety-five thousand, nine hundred four".