643170313 has 4 divisors (see below), whose sum is σ = 643420948. Its totient is φ = 642919680.

The previous prime is 643170301. The next prime is 643170343. The reversal of 643170313 is 313071346.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 530979849 + 112190464 = 23043^2 + 10592^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643170313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643170343) 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, 121428 + ... + 126613.

It is an arithmetic number, because the mean of its divisors is an integer number (160855237).

Almost surely, 2^643170313 is an apocalyptic number.

It is an amenable number.

643170313 is a deficient number, since it is larger than the sum of its proper divisors (250635).

643170313 is a wasteful number, since it uses less digits than its factorization.

643170313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250634.

The product of its (nonzero) digits is 4536, while the sum is 28.

The square root of 643170313 is about 25360.8026884009. The cubic root of 643170313 is about 863.1944979147.

The spelling of 643170313 in words is "six hundred forty-three million, one hundred seventy thousand, three hundred thirteen".