645743317 has 8 divisors (see below), whose sum is σ = 700405272. Its totient is φ = 592934400.

The previous prime is 645743303. The next prime is 645743323. The reversal of 645743317 is 713347546.

It can be written as a sum of positive squares in 4 ways, for example, as 58844241 + 586899076 = 7671^2 + 24226^2 .

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 645743317 - 2²³ = 637354709 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 645743317.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645743017) 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, 462534 + ... + 463927.

It is an arithmetic number, because the mean of its divisors is an integer number (87550659).

Almost surely, 2^645743317 is an apocalyptic number.

It is an amenable number.

645743317 is a deficient number, since it is larger than the sum of its proper divisors (54661955).

645743317 is a wasteful number, since it uses less digits than its factorization.

645743317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926519.

The product of its digits is 211680, while the sum is 40.

The square root of 645743317 is about 25411.4800238003. The cubic root of 645743317 is about 864.3440367472.

The spelling of 645743317 in words is "six hundred forty-five million, seven hundred forty-three thousand, three hundred seventeen".