256720399147 has 2 divisors, whose sum is σ = 256720399148. Its totient is φ = 256720399146.

The previous prime is 256720399127. The next prime is 256720399217. The reversal of 256720399147 is 741993027652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256720399147 - 2²⁷ = 256586181419 is a prime.

It is not a weakly prime, because it can be changed into another prime (256720399127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128360199573 + 128360199574.

It is an arithmetic number, because the mean of its divisors is an integer number (128360199574).

Almost surely, 2^256720399147 is an apocalyptic number.

256720399147 is a deficient number, since it is larger than the sum of its proper divisors (1).

256720399147 is an equidigital number, since it uses as much as digits as its factorization.

256720399147 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5715360, while the sum is 55.

The spelling of 256720399147 in words is "two hundred fifty-six billion, seven hundred twenty million, three hundred ninety-nine thousand, one hundred forty-seven".