1279129877 has 2 divisors, whose sum is σ = 1279129878. Its totient is φ = 1279129876.

The previous prime is 1279129867. The next prime is 1279129921. The reversal of 1279129877 is 7789219721.

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., 1238054596 + 41075281 = 35186^2 + 6409^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1279129877 is a prime.

It is a super-5 number, since 5×1279129877⁵ (a number of 47 digits) contains 55555 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1279129867) 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, 639564938 + 639564939.

It is an arithmetic number, because the mean of its divisors is an integer number (639564939).

Almost surely, 2^1279129877 is an apocalyptic number.

It is an amenable number.

1279129877 is a deficient number, since it is larger than the sum of its proper divisors (1).

1279129877 is an equidigital number, since it uses as much as digits as its factorization.

1279129877 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 889056, while the sum is 53.

The square root of 1279129877 is about 35764.9252340893. The cubic root of 1279129877 is about 1085.5209619931.

The spelling of 1279129877 in words is "one billion, two hundred seventy-nine million, one hundred twenty-nine thousand, eight hundred seventy-seven".