1278275649 has 8 divisors (see below), whose sum is σ = 1947848640. Its totient is φ = 730443216.

The previous prime is 1278275627. The next prime is 1278275653. The reversal of 1278275649 is 9465728721.

It is a happy number.

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

It is not a de Polignac number, because 1278275649 - 2⁵ = 1278275617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1278275699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30435114 + ... + 30435155.

It is an arithmetic number, because the mean of its divisors is an integer number (243481080).

Almost surely, 2^1278275649 is an apocalyptic number.

It is an amenable number.

1278275649 is a deficient number, since it is larger than the sum of its proper divisors (669572991).

1278275649 is an equidigital number, since it uses as much as digits as its factorization.

1278275649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60870279.

The product of its digits is 1693440, while the sum is 51.

The square root of 1278275649 is about 35752.9809806120. The cubic root of 1278275649 is about 1085.2792641242.

The spelling of 1278275649 in words is "one billion, two hundred seventy-eight million, two hundred seventy-five thousand, six hundred forty-nine".