19217364864 has 128 divisors (see below), whose sum is σ = 53886681600. Its totient is φ = 6051262464.

The previous prime is 19217364851. The next prime is 19217364871. The reversal of 19217364864 is 46846371291.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×19217364864² (a number of 21 digits) contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 2674044 + ... + 2681220.

It is an arithmetic number, because the mean of its divisors is an integer number (420989700).

Almost surely, 2^19217364864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19217364864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26943340800).

19217364864 is an abundant number, since it is smaller than the sum of its proper divisors (34669316736).

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

19217364864 is a wasteful number, since it uses less digits than its factorization.

19217364864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7580 (or 7568 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 51.

The spelling of 19217364864 in words is "nineteen billion, two hundred seventeen million, three hundred sixty-four thousand, eight hundred sixty-four".