20217859438464 has 1152 divisors, whose sum is σ = 64935862118400. Its totient is φ = 6258249216000.

The previous prime is 20217859438459. The next prime is 20217859438481. The reversal of 20217859438464 is 46483495871202.

20217859438464 is a `hidden beast` number, since 2 + 0 + 2 + 1 + 7 + 8 + 594 + 38 + 4 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a super-3 number, since 3×20217859438464³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 133893108789 + ... + 133893108939.

It is a 2-persistent number, because it is pandigital, and so is 2⋅20217859438464 = 40435718876928, but 3⋅20217859438464 = 60653578315392 is not.

Almost surely, 2^{20217859438464} is an apocalyptic number.

20217859438464 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 20217859438464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32467931059200).

20217859438464 is an abundant number, since it is smaller than the sum of its proper divisors (44718002679936).

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

20217859438464 is an equidigital number, since it uses as much as digits as its factorization.

20217859438464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 92897280, while the sum is 63.

The spelling of 20217859438464 in words is "twenty trillion, two hundred seventeen billion, eight hundred fifty-nine million, four hundred thirty-eight thousand, four hundred sixty-four".