256969873 has 2 divisors, whose sum is σ = 256969874. Its totient is φ = 256969872.

The previous prime is 256969793. The next prime is 256969877. The reversal of 256969873 is 378969652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194686209 + 62283664 = 13953^2 + 7892^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256969873 is a prime.

It is a super-3 number, since 3×256969873³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (256969877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128484936 + 128484937.

It is an arithmetic number, because the mean of its divisors is an integer number (128484937).

Almost surely, 2^256969873 is an apocalyptic number.

It is an amenable number.

256969873 is a deficient number, since it is larger than the sum of its proper divisors (1).

256969873 is an equidigital number, since it uses as much as digits as its factorization.

256969873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 55.

The square root of 256969873 is about 16030.2798790289. The cubic root of 256969873 is about 635.7612735157.

The spelling of 256969873 in words is "two hundred fifty-six million, nine hundred sixty-nine thousand, eight hundred seventy-three".