257065819 has 2 divisors, whose sum is σ = 257065820. Its totient is φ = 257065818.

The previous prime is 257065807. The next prime is 257065829. The reversal of 257065819 is 918560752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257065819 - 2¹¹ = 257063771 is a prime.

It is a super-2 number, since 2×257065819² = 132165670596281522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257065829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128532909 + 128532910.

It is an arithmetic number, because the mean of its divisors is an integer number (128532910).

Almost surely, 2^257065819 is an apocalyptic number.

257065819 is a deficient number, since it is larger than the sum of its proper divisors (1).

257065819 is an equidigital number, since it uses as much as digits as its factorization.

257065819 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 151200, while the sum is 43.

The square root of 257065819 is about 16033.2722486709. The cubic root of 257065819 is about 635.8403893542.

The spelling of 257065819 in words is "two hundred fifty-seven million, sixty-five thousand, eight hundred nineteen".