1278987449 has 8 divisors (see below), whose sum is σ = 1297455432. Its totient is φ = 1260645120.

The previous prime is 1278987433. The next prime is 1278987509. The reversal of 1278987449 is 9447898721.

It can be written as a sum of positive squares in 4 ways, for example, as 23348224 + 1255639225 = 4832^2 + 35435^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1278987449 - 2⁴ = 1278987433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1278987419) 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 in 7 ways as a sum of consecutive naturals, for example, 10814 + ... + 51719.

It is an arithmetic number, because the mean of its divisors is an integer number (162181929).

Almost surely, 2^1278987449 is an apocalyptic number.

It is an amenable number.

1278987449 is a deficient number, since it is larger than the sum of its proper divisors (18467983).

1278987449 is a wasteful number, since it uses less digits than its factorization.

1278987449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62827.

The product of its digits is 8128512, while the sum is 59.

The square root of 1278987449 is about 35762.9340099495. The cubic root of 1278987449 is about 1085.4806704582.

The spelling of 1278987449 in words is "one billion, two hundred seventy-eight million, nine hundred eighty-seven thousand, four hundred forty-nine".