509691361 has 2 divisors, whose sum is σ = 509691362. Its totient is φ = 509691360.

The previous prime is 509691251. The next prime is 509691379. The reversal of 509691361 is 163196905.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 422549136 + 87142225 = 20556^2 + 9335^2 .

It is a cyclic number.

It is not a de Polignac number, because 509691361 - 2⁷ = 509691233 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (509601361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 254845680 + 254845681.

It is an arithmetic number, because the mean of its divisors is an integer number (254845681).

Almost surely, 2^509691361 is an apocalyptic number.

It is an amenable number.

509691361 is a deficient number, since it is larger than the sum of its proper divisors (1).

509691361 is an equidigital number, since it uses as much as digits as its factorization.

509691361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 509691361 is about 22576.3451647958. The cubic root of 509691361 is about 798.7957720575.

The spelling of 509691361 in words is "five hundred nine million, six hundred ninety-one thousand, three hundred sixty-one".