645891052208 has 20 divisors (see below), whose sum is σ = 1251449669208. Its totient is φ = 322936298880.

The previous prime is 645891052187. The next prime is 645891052277. The reversal of 645891052208 is 802250198546.

It is a happy 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 3 ways as a sum of consecutive naturals, for example, 19460 + ... + 1136732.

Almost surely, 2^645891052208 is an apocalyptic number.

It is an amenable number.

645891052208 is a deficient number, since it is larger than the sum of its proper divisors (605558617000).

645891052208 is a wasteful number, since it uses less digits than its factorization.

645891052208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1153412 (or 1153406 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 50.

The spelling of 645891052208 in words is "six hundred forty-five billion, eight hundred ninety-one million, fifty-two thousand, two hundred eight".