256252662181 has 2 divisors, whose sum is σ = 256252662182. Its totient is φ = 256252662180.

The previous prime is 256252662121. The next prime is 256252662209. The reversal of 256252662181 is 181266252652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155341609956 + 100911052225 = 394134^2 + 317665^2 .

It is a cyclic number.

It is not a de Polignac number, because 256252662181 - 2¹³ = 256252653989 is a prime.

It is a super-2 number, since 2×256252662181² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256252662101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128126331090 + 128126331091.

It is an arithmetic number, because the mean of its divisors is an integer number (128126331091).

Almost surely, 2^256252662181 is an apocalyptic number.

It is an amenable number.

256252662181 is a deficient number, since it is larger than the sum of its proper divisors (1).

256252662181 is an equidigital number, since it uses as much as digits as its factorization.

256252662181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 691200, while the sum is 46.

The spelling of 256252662181 in words is "two hundred fifty-six billion, two hundred fifty-two million, six hundred sixty-two thousand, one hundred eighty-one".