1255621979 has 2 divisors, whose sum is σ = 1255621980. Its totient is φ = 1255621978.

The previous prime is 1255621963. The next prime is 1255621981. The reversal of 1255621979 is 9791265521.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1255621979 - 2⁴ = 1255621963 is a prime.

Together with 1255621981, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1255641979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 627810989 + 627810990.

It is an arithmetic number, because the mean of its divisors is an integer number (627810990).

Almost surely, 2^1255621979 is an apocalyptic number.

1255621979 is a deficient number, since it is larger than the sum of its proper divisors (1).

1255621979 is an equidigital number, since it uses as much as digits as its factorization.

1255621979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 340200, while the sum is 47.

The square root of 1255621979 is about 35434.7566521911. The cubic root of 1255621979 is about 1078.8298881224.

The spelling of 1255621979 in words is "one billion, two hundred fifty-five million, six hundred twenty-one thousand, nine hundred seventy-nine".