513997668 has 36 divisors (see below), whose sum is σ = 1304126460. Its totient is φ = 170692416.

The previous prime is 513997663. The next prime is 513997739. The reversal of 513997668 is 866799315.

It can be written as a sum of positive squares in 2 ways, for example, as 20358144 + 493639524 = 4512^2 + 22218^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (513997663) 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, 16855 + ... + 36222.

It is an arithmetic number, because the mean of its divisors is an integer number (36225735).

Almost surely, 2^513997668 is an apocalyptic number.

It is an amenable number.

513997668 is an abundant number, since it is smaller than the sum of its proper divisors (790128792).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

513997668 is a wasteful number, since it uses less digits than its factorization.

513997668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53356 (or 53351 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The square root of 513997668 is about 22671.5166673957. The cubic root of 513997668 is about 801.0391018332.

The spelling of 513997668 in words is "five hundred thirteen million, nine hundred ninety-seven thousand, six hundred sixty-eight".