513691 has 2 divisors, whose sum is σ = 513692. Its totient is φ = 513690.

The previous prime is 513683. The next prime is 513697. The reversal of 513691 is 196315.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 513691 - 2³ = 513683 is a prime.

It is not a weakly prime, because it can be changed into another prime (513697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256845 + 256846.

It is an arithmetic number, because the mean of its divisors is an integer number (256846).

2⁵¹³⁶⁹¹ is an apocalyptic number.

513691 is a deficient number, since it is larger than the sum of its proper divisors (1).

513691 is an equidigital number, since it uses as much as digits as its factorization.

513691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 810, while the sum is 25.

The square root of 513691 is about 716.7224009336. The cubic root of 513691 is about 80.0879761337.

The spelling of 513691 in words is "five hundred thirteen thousand, six hundred ninety-one".