645700576640 has 128 divisors (see below), whose sum is σ = 1805173413120. Its totient is φ = 216234547200.

The previous prime is 645700576607. The next prime is 645700576693. The reversal of 645700576640 is 46675007546.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1483286 + ... + 1868565.

It is an arithmetic number, because the mean of its divisors is an integer number (14102917290).

Almost surely, 2^645700576640 is an apocalyptic number.

It is an amenable number.

645700576640 is an abundant number, since it is smaller than the sum of its proper divisors (1159472836480).

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

645700576640 is a wasteful number, since it uses less digits than its factorization.

645700576640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3351920 (or 3351908 counting only the distinct ones).

The product of its (nonzero) digits is 4233600, while the sum is 50.

The spelling of 645700576640 in words is "six hundred forty-five billion, seven hundred million, five hundred seventy-six thousand, six hundred forty".