645607913 has 8 divisors (see below), whose sum is σ = 666353760. Its totient is φ = 625188960.

The previous prime is 645607903. The next prime is 645607927. The reversal of 645607913 is 319706546.

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 645607913 - 2²⁶ = 578499049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645607903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77708 + ... + 85613.

It is an arithmetic number, because the mean of its divisors is an integer number (83294220).

Almost surely, 2^645607913 is an apocalyptic number.

It is an amenable number.

645607913 is a deficient number, since it is larger than the sum of its proper divisors (20745847).

645607913 is a wasteful number, since it uses less digits than its factorization.

645607913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163447.

The product of its (nonzero) digits is 136080, while the sum is 41.

The square root of 645607913 is about 25408.8156552012. The cubic root of 645607913 is about 864.2836186119.

The spelling of 645607913 in words is "six hundred forty-five million, six hundred seven thousand, nine hundred thirteen".