256169 has 2 divisors, whose sum is σ = 256170. Its totient is φ = 256168.

The previous prime is 256163. The next prime is 256181. The reversal of 256169 is 961652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 150544 + 105625 = 388^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 256169 - 2¹⁶ = 190633 is a prime.

It is a super-2 number, since 2×256169² = 131245113122, which contains 22 as substring.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (256163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128084 + 128085.

It is an arithmetic number, because the mean of its divisors is an integer number (128085).

2²⁵⁶¹⁶⁹ is an apocalyptic number.

It is an amenable number.

256169 is a deficient number, since it is larger than the sum of its proper divisors (1).

256169 is an equidigital number, since it uses as much as digits as its factorization.

256169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3240, while the sum is 29.

The square root of 256169 is about 506.1314058622. The cubic root of 256169 is about 63.5100114415.

It can be divided in two parts, 256 and 169, that multiplied together give a square (43264 = 208²).

The spelling of 256169 in words is "two hundred fifty-six thousand, one hundred sixty-nine".