256336139 has 2 divisors, whose sum is σ = 256336140. Its totient is φ = 256336138.

The previous prime is 256336123. The next prime is 256336147. The reversal of 256336139 is 931633652.

256336139 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 is a cyclic number.

It is not a de Polignac number, because 256336139 - 2⁴ = 256336123 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (256336159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128168069 + 128168070.

It is an arithmetic number, because the mean of its divisors is an integer number (128168070).

Almost surely, 2^256336139 is an apocalyptic number.

256336139 is a deficient number, since it is larger than the sum of its proper divisors (1).

256336139 is an equidigital number, since it uses as much as digits as its factorization.

256336139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 38.

The square root of 256336139 is about 16010.5008978483. The cubic root of 256336139 is about 635.2382093453.

The spelling of 256336139 in words is "two hundred fifty-six million, three hundred thirty-six thousand, one hundred thirty-nine".