256309771 has 2 divisors, whose sum is σ = 256309772. Its totient is φ = 256309770.

The previous prime is 256309759. The next prime is 256309783. The reversal of 256309771 is 177903652.

It is a balanced prime because it is at equal distance from previous prime (256309759) and next prime (256309783).

It is a cyclic number.

It is not a de Polignac number, because 256309771 - 2¹³ = 256301579 is a prime.

It is not a weakly prime, because it can be changed into another prime (256309751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128154885 + 128154886.

It is an arithmetic number, because the mean of its divisors is an integer number (128154886).

Almost surely, 2^256309771 is an apocalyptic number.

256309771 is a deficient number, since it is larger than the sum of its proper divisors (1).

256309771 is an equidigital number, since it uses as much as digits as its factorization.

256309771 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 79380, while the sum is 40.

The square root of 256309771 is about 16009.6774171124. The cubic root of 256309771 is about 635.2164273529.

The spelling of 256309771 in words is "two hundred fifty-six million, three hundred nine thousand, seven hundred seventy-one".