646431613 has 16 divisors (see below), whose sum is σ = 693743616. Its totient is φ = 600198400.

The previous prime is 646431601. The next prime is 646431637. The reversal of 646431613 is 316134646.

It is a cyclic number.

It is not a de Polignac number, because 646431613 - 2⁵ = 646431581 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646431913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 657120 + ... + 658102.

It is an arithmetic number, because the mean of its divisors is an integer number (43358976).

Almost surely, 2^646431613 is an apocalyptic number.

It is an amenable number.

646431613 is a deficient number, since it is larger than the sum of its proper divisors (47312003).

646431613 is a wasteful number, since it uses less digits than its factorization.

646431613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1484.

The product of its digits is 31104, while the sum is 34.

The square root of 646431613 is about 25425.0194296878. The cubic root of 646431613 is about 864.6510283316.

The spelling of 646431613 in words is "six hundred forty-six million, four hundred thirty-one thousand, six hundred thirteen".