1255523981 has 2 divisors, whose sum is σ = 1255523982. Its totient is φ = 1255523980.

The previous prime is 1255523939. The next prime is 1255523989. The reversal of 1255523981 is 1893255521.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1071514756 + 184009225 = 32734^2 + 13565^2 .

It is a cyclic number.

It is not a de Polignac number, because 1255523981 - 2⁶ = 1255523917 is a prime.

It is a super-2 number, since 2×1255523981² = 3152680933732176722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1255523989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 627761990 + 627761991.

It is an arithmetic number, because the mean of its divisors is an integer number (627761991).

Almost surely, 2^1255523981 is an apocalyptic number.

It is an amenable number.

1255523981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1255523981 is an equidigital number, since it uses as much as digits as its factorization.

1255523981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108000, while the sum is 41.

The square root of 1255523981 is about 35433.3738303312. The cubic root of 1255523981 is about 1078.8018207784.

The spelling of 1255523981 in words is "one billion, two hundred fifty-five million, five hundred twenty-three thousand, nine hundred eighty-one".