645966373647 has 32 divisors (see below), whose sum is σ = 994955157504. Its totient is φ = 365142758400.

The previous prime is 645966373627. The next prime is 645966373681. The reversal of 645966373647 is 746373669546.

It is not a de Polignac number, because 645966373647 - 2⁶ = 645966373583 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645966373607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4224997 + ... + 4375217.

It is an arithmetic number, because the mean of its divisors is an integer number (31092348672).

Almost surely, 2^645966373647 is an apocalyptic number.

645966373647 is a deficient number, since it is larger than the sum of its proper divisors (348988783857).

645966373647 is a wasteful number, since it uses less digits than its factorization.

645966373647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152439.

The product of its digits is 411505920, while the sum is 66.

The spelling of 645966373647 in words is "six hundred forty-five billion, nine hundred sixty-six million, three hundred seventy-three thousand, six hundred forty-seven".