1279518157 has 2 divisors, whose sum is σ = 1279518158. Its totient is φ = 1279518156.

The previous prime is 1279518139. The next prime is 1279518167. The reversal of 1279518157 is 7518159721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 698756356 + 580761801 = 26434^2 + 24099^2 .

It is an emirp because it is prime and its reverse (7518159721) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1279518157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1279518167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639759078 + 639759079.

It is an arithmetic number, because the mean of its divisors is an integer number (639759079).

Almost surely, 2^1279518157 is an apocalyptic number.

It is an amenable number.

1279518157 is a deficient number, since it is larger than the sum of its proper divisors (1).

1279518157 is an equidigital number, since it uses as much as digits as its factorization.

1279518157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 176400, while the sum is 46.

The square root of 1279518157 is about 35770.3530455040. The cubic root of 1279518157 is about 1085.6307875463.

The spelling of 1279518157 in words is "one billion, two hundred seventy-nine million, five hundred eighteen thousand, one hundred fifty-seven".