645612313345 has 4 divisors (see below), whose sum is σ = 774734776020. Its totient is φ = 516489850672.

The previous prime is 645612313337. The next prime is 645612313373. The reversal of 645612313345 is 543313216546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 368954197056 + 276658116289 = 607416^2 + 525983^2 .

It is a cyclic number.

It is not a de Polignac number, because 645612313345 - 2³ = 645612313337 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64561231330 + ... + 64561231339.

It is an arithmetic number, because the mean of its divisors is an integer number (193683694005).

Almost surely, 2^645612313345 is an apocalyptic number.

It is an amenable number.

645612313345 is a deficient number, since it is larger than the sum of its proper divisors (129122462675).

645612313345 is a wasteful number, since it uses less digits than its factorization.

645612313345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129122462674.

The product of its digits is 777600, while the sum is 43.

The spelling of 645612313345 in words is "six hundred forty-five billion, six hundred twelve million, three hundred thirteen thousand, three hundred forty-five".