645245563117 has 4 divisors (see below), whose sum is σ = 645251580576. Its totient is φ = 645239545660.

The previous prime is 645245563099. The next prime is 645245563163. The reversal of 645245563117 is 711365542546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645245563117 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645245563177) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2844913 + ... + 3063334.

It is an arithmetic number, because the mean of its divisors is an integer number (161312895144).

Almost surely, 2^645245563117 is an apocalyptic number.

It is an amenable number.

645245563117 is a deficient number, since it is larger than the sum of its proper divisors (6017459).

645245563117 is a wasteful number, since it uses less digits than its factorization.

645245563117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6017458.

The product of its digits is 3024000, while the sum is 49.

The spelling of 645245563117 in words is "six hundred forty-five billion, two hundred forty-five million, five hundred sixty-three thousand, one hundred seventeen".