1255695121 has 2 divisors, whose sum is σ = 1255695122. Its totient is φ = 1255695120.

The previous prime is 1255695107. The next prime is 1255695169. The reversal of 1255695121 is 1215965521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 900900225 + 354794896 = 30015^2 + 18836^2 .

It is a cyclic number.

It is not a de Polignac number, because 1255695121 - 2²³ = 1247306513 is a prime.

It is not a weakly prime, because it can be changed into another prime (1255395121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 627847560 + 627847561.

It is an arithmetic number, because the mean of its divisors is an integer number (627847561).

Almost surely, 2^1255695121 is an apocalyptic number.

It is an amenable number.

1255695121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1255695121 is an equidigital number, since it uses as much as digits as its factorization.

1255695121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27000, while the sum is 37.

The square root of 1255695121 is about 35435.7887029483. The cubic root of 1255695121 is about 1078.8508355744.

The spelling of 1255695121 in words is "one billion, two hundred fifty-five million, six hundred ninety-five thousand, one hundred twenty-one".