646984313 has 4 divisors (see below), whose sum is σ = 648061428. Its totient is φ = 645907200.

The previous prime is 646984309. The next prime is 646984337. The reversal of 646984313 is 313489646.

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 481012624 + 165971689 = 21932^2 + 12883^2 .

It is a cyclic number.

It is not a de Polignac number, because 646984313 - 2² = 646984309 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646984363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537656 + ... + 538857.

It is an arithmetic number, because the mean of its divisors is an integer number (162015357).

Almost surely, 2^646984313 is an apocalyptic number.

It is an amenable number.

646984313 is a deficient number, since it is larger than the sum of its proper divisors (1077115).

646984313 is a wasteful number, since it uses less digits than its factorization.

646984313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1077114.

The product of its digits is 373248, while the sum is 44.

The square root of 646984313 is about 25435.8863222810. The cubic root of 646984313 is about 864.8973841094.

The spelling of 646984313 in words is "six hundred forty-six million, nine hundred eighty-four thousand, three hundred thirteen".