256220369 has 2 divisors, whose sum is σ = 256220370. Its totient is φ = 256220368.

The previous prime is 256220351. The next prime is 256220387. The reversal of 256220369 is 963022652.

It is a balanced prime because it is at equal distance from previous prime (256220351) and next prime (256220387).

It can be written as a sum of positive squares in only one way, i.e., 234243025 + 21977344 = 15305^2 + 4688^2 .

It is a cyclic number.

It is not a de Polignac number, because 256220369 - 2⁸ = 256220113 is a prime.

It is a super-2 number, since 2×256220369² = 131297754980992322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (256220309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128110184 + 128110185.

It is an arithmetic number, because the mean of its divisors is an integer number (128110185).

Almost surely, 2^256220369 is an apocalyptic number.

It is an amenable number.

256220369 is a deficient number, since it is larger than the sum of its proper divisors (1).

256220369 is an equidigital number, since it uses as much as digits as its factorization.

256220369 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 35.

The square root of 256220369 is about 16006.8850498778. The cubic root of 256220369 is about 635.1425633160.

The spelling of 256220369 in words is "two hundred fifty-six million, two hundred twenty thousand, three hundred sixty-nine".