509656831 has 2 divisors, whose sum is σ = 509656832. Its totient is φ = 509656830.

The previous prime is 509656813. The next prime is 509656841. The reversal of 509656831 is 138656905.

Together with previous prime (509656813) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 509656831 - 2⁹ = 509656319 is a prime.

It is a super-2 number, since 2×509656831² = 519500170769925122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (509656841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254828415 + 254828416.

It is an arithmetic number, because the mean of its divisors is an integer number (254828416).

Almost surely, 2^509656831 is an apocalyptic number.

509656831 is a deficient number, since it is larger than the sum of its proper divisors (1).

509656831 is an equidigital number, since it uses as much as digits as its factorization.

509656831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 194400, while the sum is 43.

The square root of 509656831 is about 22575.5804133581. The cubic root of 509656831 is about 798.7777330095. Note that the first 4 decimals are identical.

The spelling of 509656831 in words is "five hundred nine million, six hundred fifty-six thousand, eight hundred thirty-one".