20645184391568 has 120 divisors (see below), whose sum is σ = 44232702925824. Its totient is φ = 9327630526720.

The previous prime is 20645184391567. The next prime is 20645184391577. The reversal of 20645184391568 is 86519348154602.

It is a self number, because there is not a number n which added to its sum of digits gives 20645184391568.

It is not an unprimeable number, because it can be changed into a prime (20645184391567) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 217208471 + ... + 217303497.

Almost surely, 2^{20645184391568} 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 20645184391568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22116351462912).

20645184391568 is an abundant number, since it is smaller than the sum of its proper divisors (23587518534256).

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

20645184391568 is a wasteful number, since it uses less digits than its factorization.

20645184391568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95733 (or 95716 counting only the distinct ones).

The product of its (nonzero) digits is 49766400, while the sum is 62.

The spelling of 20645184391568 in words is "twenty trillion, six hundred forty-five billion, one hundred eighty-four million, three hundred ninety-one thousand, five hundred sixty-eight".