1257275779 has 2 divisors, whose sum is σ = 1257275780. Its totient is φ = 1257275778.

The previous prime is 1257275741. The next prime is 1257275797. The reversal of 1257275779 is 9775727521.

Together with next prime (1257275797) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1257275779 - 2⁹ = 1257275267 is a prime.

It is not a weakly prime, because it can be changed into another prime (1257275729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628637889 + 628637890.

It is an arithmetic number, because the mean of its divisors is an integer number (628637890).

Almost surely, 2^1257275779 is an apocalyptic number.

1257275779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257275779 is an equidigital number, since it uses as much as digits as its factorization.

1257275779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160900, while the sum is 52.

The square root of 1257275779 is about 35458.0848185572. The cubic root of 1257275779 is about 1079.3033284179.

The spelling of 1257275779 in words is "one billion, two hundred fifty-seven million, two hundred seventy-five thousand, seven hundred seventy-nine".