646313 has 4 divisors (see below), whose sum is σ = 655488. Its totient is φ = 637140.

The previous prime is 646309. The next prime is 646339. The reversal of 646313 is 313646.

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: 313646 = 2 ⋅156823.

It is a cyclic number.

It is not a de Polignac number, because 646313 - 2² = 646309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4481 + ... + 4622.

It is an arithmetic number, because the mean of its divisors is an integer number (163872).

2⁶⁴⁶³¹³ is an apocalyptic number.

It is an amenable number.

646313 is a deficient number, since it is larger than the sum of its proper divisors (9175).

646313 is an equidigital number, since it uses as much as digits as its factorization.

646313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9174.

The product of its digits is 1296, while the sum is 23.

The square root of 646313 is about 803.9359427218. The cubic root of 646313 is about 86.4598140486.

Adding to 646313 its reverse (313646), we get a palindrome (959959).

It can be divided in two parts, 646 and 313, that added together give a palindrome (959).

The spelling of 646313 in words is "six hundred forty-six thousand, three hundred thirteen".