256101869 has 2 divisors, whose sum is σ = 256101870. Its totient is φ = 256101868.

The previous prime is 256101863. The next prime is 256101877. The reversal of 256101869 is 968101652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 243048100 + 13053769 = 15590^2 + 3613^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256101869 is a prime.

It is a super-2 number, since 2×256101869² = 131176334610586322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256101863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128050934 + 128050935.

It is an arithmetic number, because the mean of its divisors is an integer number (128050935).

Almost surely, 2^256101869 is an apocalyptic number.

It is an amenable number.

256101869 is a deficient number, since it is larger than the sum of its proper divisors (1).

256101869 is an equidigital number, since it uses as much as digits as its factorization.

256101869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 256101869 is about 16003.1830896231. The cubic root of 256101869 is about 635.0446319922.

The spelling of 256101869 in words is "two hundred fifty-six million, one hundred one thousand, eight hundred sixty-nine".