513520921 has 27 divisors (see below), whose sum is σ = 577082943. Its totient is φ = 456845760.

The previous prime is 513520907. The next prime is 513520933. The reversal of 513520921 is 129025315.

The square root of 513520921 is 22661.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 399800025 + 113720896 = 19995^2 + 10664^2 .

It is not a de Polignac number, because 513520921 - 2¹³ = 513512729 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 513520921.

It is not an unprimeable number, because it can be changed into a prime (513520321) 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 26 ways as a sum of consecutive naturals, for example, 11942326 + ... + 11942368.

Almost surely, 2^513520921 is an apocalyptic number.

513520921 is the 22661-st square number.

513520921 is the 11331-st centered octagonal number.

It is an amenable number.

513520921 is a deficient number, since it is larger than the sum of its proper divisors (63562022).

513520921 is an equidigital number, since it uses as much as digits as its factorization.

513520921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 28.

The cubic root of 513520921 is about 800.7913632763.

The spelling of 513520921 in words is "five hundred thirteen million, five hundred twenty thousand, nine hundred twenty-one".