645163515517 has 8 divisors (see below), whose sum is σ = 670836379392. Its totient is φ = 619794472800.

The previous prime is 645163515497. The next prime is 645163515547. The reversal of 645163515517 is 715515361546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645163515517 - 2⁷ = 645163515389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645163515547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75950959 + ... + 75959452.

It is an arithmetic number, because the mean of its divisors is an integer number (83854547424).

Almost surely, 2^645163515517 is an apocalyptic number.

It is an amenable number.

645163515517 is a deficient number, since it is larger than the sum of its proper divisors (25672863875).

645163515517 is a wasteful number, since it uses less digits than its factorization.

645163515517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151910579.

The product of its digits is 1890000, while the sum is 49.

The spelling of 645163515517 in words is "six hundred forty-five billion, one hundred sixty-three million, five hundred fifteen thousand, five hundred seventeen".