645321672175 has 48 divisors (see below), whose sum is σ = 824631363072. Its totient is φ = 500593564800.

The previous prime is 645321672157. The next prime is 645321672181. The reversal of 645321672175 is 571276123546.

It is not a de Polignac number, because 645321672175 - 2⁹ = 645321671663 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 664594440 + ... + 664595410.

It is an arithmetic number, because the mean of its divisors is an integer number (17179820064).

Almost surely, 2^645321672175 is an apocalyptic number.

645321672175 is a deficient number, since it is larger than the sum of its proper divisors (179309690897).

645321672175 is a wasteful number, since it uses less digits than its factorization.

645321672175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2728 (or 2723 counting only the distinct ones).

The product of its digits is 2116800, while the sum is 49.

The spelling of 645321672175 in words is "six hundred forty-five billion, three hundred twenty-one million, six hundred seventy-two thousand, one hundred seventy-five".