513664 has 16 divisors (see below), whose sum is σ = 1023570. Its totient is φ = 256768.

The previous prime is 513649. The next prime is 513673. The reversal of 513664 is 466315.

It can be written as a sum of positive squares in only one way, i.e., 360000 + 153664 = 600^2 + 392^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is an unprimeable number.

513664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1879 + ... + 2134.

2⁵¹³⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

513664 is a deficient number, since it is larger than the sum of its proper divisors (509906).

513664 is an equidigital number, since it uses as much as digits as its factorization.

513664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4027 (or 4015 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 513664 is about 716.7035649416. The cubic root of 513664 is about 80.0865729469.

Adding to 513664 its reverse (466315), we get a palindrome (979979).

The spelling of 513664 in words is "five hundred thirteen thousand, six hundred sixty-four".