646641513 has 12 divisors (see below), whose sum is σ = 1067471808. Its totient is φ = 369509400.

The previous prime is 646641469. The next prime is 646641521. The reversal of 646641513 is 315146646.

It is a happy number.

646641513 is a `hidden beast` number, since 6 + 4 + 6 + 641 + 5 + 1 + 3 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-646641513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (646641533) 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 11 ways as a sum of consecutive naturals, for example, 5132013 + ... + 5132138.

It is an arithmetic number, because the mean of its divisors is an integer number (88955984).

Almost surely, 2^646641513 is an apocalyptic number.

646641513 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

646641513 is a deficient number, since it is larger than the sum of its proper divisors (420830295).

646641513 is a wasteful number, since it uses less digits than its factorization.

646641513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10264164 (or 10264161 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 646641513 is about 25429.1469184477. The cubic root of 646641513 is about 864.7446038968.

The spelling of 646641513 in words is "six hundred forty-six million, six hundred forty-one thousand, five hundred thirteen".