645370313 has 4 divisors (see below), whose sum is σ = 737566080. Its totient is φ = 553174548.

The previous prime is 645370289. The next prime is 645370399. The reversal of 645370313 is 313073546.

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, and also an emirpimes, since its reverse is a distinct semiprime: 313073546 = 2 ⋅156536773.

It is a cyclic number.

It is not a de Polignac number, because 645370313 - 2⁶ = 645370249 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 645370313.

It is not an unprimeable number, because it can be changed into a prime (645370013) 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, 46097873 + ... + 46097886.

It is an arithmetic number, because the mean of its divisors is an integer number (184391520).

Almost surely, 2^645370313 is an apocalyptic number.

It is an amenable number.

645370313 is a deficient number, since it is larger than the sum of its proper divisors (92195767).

645370313 is an equidigital number, since it uses as much as digits as its factorization.

645370313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92195766.

The product of its (nonzero) digits is 22680, while the sum is 32.

The square root of 645370313 is about 25404.1396823431. The cubic root of 645370313 is about 864.1775795436.

The spelling of 645370313 in words is "six hundred forty-five million, three hundred seventy thousand, three hundred thirteen".