257206361 has 2 divisors, whose sum is σ = 257206362. Its totient is φ = 257206360.

The previous prime is 257206291. The next prime is 257206381. The reversal of 257206361 is 163602752.

257206361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 163968025 + 93238336 = 12805^2 + 9656^2 .

It is a cyclic number.

It is not a de Polignac number, because 257206361 - 2²² = 253012057 is a prime.

It is a super-2 number, since 2×257206361² = 132310224277724642, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257206381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128603180 + 128603181.

It is an arithmetic number, because the mean of its divisors is an integer number (128603181).

Almost surely, 2^257206361 is an apocalyptic number.

It is an amenable number.

257206361 is a deficient number, since it is larger than the sum of its proper divisors (1).

257206361 is an equidigital number, since it uses as much as digits as its factorization.

257206361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 257206361 is about 16037.6544731454. The cubic root of 257206361 is about 635.9562429516.

The spelling of 257206361 in words is "two hundred fifty-seven million, two hundred six thousand, three hundred sixty-one".