686270257 has 2 divisors, whose sum is σ = 686270258. Its totient is φ = 686270256.

The previous prime is 686270203. The next prime is 686270293. The reversal of 686270257 is 752072686.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 618964641 + 67305616 = 24879^2 + 8204^2 .

It is a cyclic number.

It is not a de Polignac number, because 686270257 - 2¹⁹ = 685745969 is a prime.

It is not a weakly prime, because it can be changed into another prime (686970257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343135128 + 343135129.

It is an arithmetic number, because the mean of its divisors is an integer number (343135129).

Almost surely, 2^686270257 is an apocalyptic number.

It is an amenable number.

686270257 is a deficient number, since it is larger than the sum of its proper divisors (1).

686270257 is an equidigital number, since it uses as much as digits as its factorization.

686270257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 282240, while the sum is 43.

The square root of 686270257 is about 26196.7604294882. The cubic root of 686270257 is about 882.0605368918.

The spelling of 686270257 in words is "six hundred eighty-six million, two hundred seventy thousand, two hundred fifty-seven".