513021 has 4 divisors (see below), whose sum is σ = 684032. Its totient is φ = 342012.

The previous prime is 513017. The next prime is 513031. The reversal of 513021 is 120315.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 513021 - 2² = 513017 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

513021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 512988 and 513006.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 513021.

It is not an unprimeable number, because it can be changed into a prime (513001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85501 + ... + 85506.

It is an arithmetic number, because the mean of its divisors is an integer number (171008).

2⁵¹³⁰²¹ is an apocalyptic number.

It is an amenable number.

513021 is a deficient number, since it is larger than the sum of its proper divisors (171011).

513021 is a wasteful number, since it uses less digits than its factorization.

513021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171010.

The product of its (nonzero) digits is 30, while the sum is 12.

The square root of 513021 is about 716.2548429156. The cubic root of 513021 is about 80.0531417749.

Adding to 513021 its reverse (120315), we get a palindrome (633336).

It can be divided in two parts, 5130 and 21, that added together give a triangular number (5151 = T₁₀₁).

The spelling of 513021 in words is "five hundred thirteen thousand, twenty-one".