645935195617 has 32 divisors (see below), whose sum is σ = 695980771200. Its totient is φ = 597639587328.

The previous prime is 645935195569. The next prime is 645935195639. The reversal of 645935195617 is 716591539546.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645935195617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645935195657) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 189255603 + ... + 189259015.

It is an arithmetic number, because the mean of its divisors is an integer number (21749399100).

Almost surely, 2^645935195617 is an apocalyptic number.

It is an amenable number.

645935195617 is a deficient number, since it is larger than the sum of its proper divisors (50045575583).

645935195617 is a wasteful number, since it uses less digits than its factorization.

645935195617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4545.

The product of its digits is 30618000, while the sum is 61.

The spelling of 645935195617 in words is "six hundred forty-five billion, nine hundred thirty-five million, one hundred ninety-five thousand, six hundred seventeen".