257364509 has 2 divisors, whose sum is σ = 257364510. Its totient is φ = 257364508.

The previous prime is 257364469. The next prime is 257364517. The reversal of 257364509 is 905463752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 250588900 + 6775609 = 15830^2 + 2603^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257364509 is a prime.

It is a super-2 number, since 2×257364509² = 132472980985622162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257364539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128682254 + 128682255.

It is an arithmetic number, because the mean of its divisors is an integer number (128682255).

Almost surely, 2^257364509 is an apocalyptic number.

It is an amenable number.

257364509 is a deficient number, since it is larger than the sum of its proper divisors (1).

257364509 is an equidigital number, since it uses as much as digits as its factorization.

257364509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 226800, while the sum is 41.

The square root of 257364509 is about 16042.5842369613. The cubic root of 257364509 is about 636.0865593262.

The spelling of 257364509 in words is "two hundred fifty-seven million, three hundred sixty-four thousand, five hundred nine".