513281 has 8 divisors (see below), whose sum is σ = 550440. Its totient is φ = 476928.

The previous prime is 513277. The next prime is 513283. The reversal of 513281 is 182315.

It can be written as a sum of positive squares in 4 ways, for example, as 102400 + 410881 = 320^2 + 641^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 513281 - 2² = 513277 is a prime.

It is a super-2 number, since 2×513281² = 526914769922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (513283) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1715 + ... + 1991.

It is an arithmetic number, because the mean of its divisors is an integer number (68805).

2⁵¹³²⁸¹ is an apocalyptic number.

It is an amenable number.

513281 is a deficient number, since it is larger than the sum of its proper divisors (37159).

513281 is a wasteful number, since it uses less digits than its factorization.

513281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403.

The product of its digits is 240, while the sum is 20.

The square root of 513281 is about 716.4363195707. The cubic root of 513281 is about 80.0666631848.

Adding to 513281 its reverse (182315), we get a palindrome (695596).

It can be divided in two parts, 51 and 3281, that multiplied together give a triangular number (167331 = T₅₇₈).

The spelling of 513281 in words is "five hundred thirteen thousand, two hundred eighty-one".