513655668 has 120 divisors (see below), whose sum is σ = 1390435200. Its totient is φ = 165255552.

The previous prime is 513655631. The next prime is 513655669. The reversal of 513655668 is 866556315.

513655668 is a `hidden beast` number, since 5 + 1 + 36 + 556 + 68 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (513655669) 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 39 ways as a sum of consecutive naturals, for example, 1355103 + ... + 1355481.

It is an arithmetic number, because the mean of its divisors is an integer number (11586960).

Almost surely, 2^513655668 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 513655668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (695217600).

513655668 is an abundant number, since it is smaller than the sum of its proper divisors (876779532).

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

513655668 is a wasteful number, since it uses less digits than its factorization.

513655668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 520 counting only the distinct ones).

The product of its digits is 648000, while the sum is 45.

The square root of 513655668 is about 22663.9729085613. The cubic root of 513655668 is about 800.8613992396.

The spelling of 513655668 in words is "five hundred thirteen million, six hundred fifty-five thousand, six hundred sixty-eight".