256214209 has 2 divisors, whose sum is σ = 256214210. Its totient is φ = 256214208.

The previous prime is 256214173. The next prime is 256214237. The reversal of 256214209 is 902412652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 242487184 + 13727025 = 15572^2 + 3705^2 .

It is a cyclic number.

It is not a de Polignac number, because 256214209 - 2¹³ = 256206017 is a prime.

It is not a weakly prime, because it can be changed into another prime (256214269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128107104 + 128107105.

It is an arithmetic number, because the mean of its divisors is an integer number (128107105).

Almost surely, 2^256214209 is an apocalyptic number.

It is an amenable number.

256214209 is a deficient number, since it is larger than the sum of its proper divisors (1).

256214209 is an equidigital number, since it uses as much as digits as its factorization.

256214209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 256214209 is about 16006.6926315214. The cubic root of 256214209 is about 635.1374732841.

The spelling of 256214209 in words is "two hundred fifty-six million, two hundred fourteen thousand, two hundred nine".