256205407 has 2 divisors, whose sum is σ = 256205408. Its totient is φ = 256205406.

The previous prime is 256205381. The next prime is 256205449. The reversal of 256205407 is 704502652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256205407 - 2¹¹ = 256203359 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256205497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128102703 + 128102704.

It is an arithmetic number, because the mean of its divisors is an integer number (128102704).

Almost surely, 2^256205407 is an apocalyptic number.

256205407 is a deficient number, since it is larger than the sum of its proper divisors (1).

256205407 is an equidigital number, since it uses as much as digits as its factorization.

256205407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 31.

The square root of 256205407 is about 16006.4176816676. The cubic root of 256205407 is about 635.1302000158.

The spelling of 256205407 in words is "two hundred fifty-six million, two hundred five thousand, four hundred seven".