645389455872 has 80 divisors (see below), whose sum is σ = 1964980429632. Its totient is φ = 184396984320.

The previous prime is 645389455847. The next prime is 645389455889. The reversal of 645389455872 is 278554983546.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30001779 + ... + 30023282.

Almost surely, 2^645389455872 is an apocalyptic number.

It is an amenable number.

645389455872 is an abundant number, since it is smaller than the sum of its proper divisors (1319590973760).

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

645389455872 is an equidigital number, since it uses as much as digits as its factorization.

645389455872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60025089 (or 60025073 counting only the distinct ones).

The product of its digits is 290304000, while the sum is 66.

The spelling of 645389455872 in words is "six hundred forty-five billion, three hundred eighty-nine million, four hundred fifty-five thousand, eight hundred seventy-two".