1278952849 has 2 divisors, whose sum is σ = 1278952850. Its totient is φ = 1278952848.

The previous prime is 1278952847. The next prime is 1278952903. The reversal of 1278952849 is 9482598721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1104897600 + 174055249 = 33240^2 + 13193^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278952849 - 2¹ = 1278952847 is a prime.

Together with 1278952847, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1278952849.

It is not a weakly prime, because it can be changed into another prime (1278952847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639476424 + 639476425.

It is an arithmetic number, because the mean of its divisors is an integer number (639476425).

Almost surely, 2^1278952849 is an apocalyptic number.

It is an amenable number.

1278952849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278952849 is an equidigital number, since it uses as much as digits as its factorization.

1278952849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2903040, while the sum is 55.

The square root of 1278952849 is about 35762.4502656068. The cubic root of 1278952849 is about 1085.4708819936.

The spelling of 1278952849 in words is "one billion, two hundred seventy-eight million, nine hundred fifty-two thousand, eight hundred forty-nine".