1278845889 has 8 divisors (see below), whose sum is σ = 1741407360. Its totient is φ = 834424176.

The previous prime is 1278845873. The next prime is 1278845899. The reversal of 1278845889 is 9885488721.

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

It is not a de Polignac number, because 1278845889 - 2⁴ = 1278845873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1278845899) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4534774 + ... + 4535055.

It is an arithmetic number, because the mean of its divisors is an integer number (217675920).

Almost surely, 2^1278845889 is an apocalyptic number.

It is an amenable number.

1278845889 is a deficient number, since it is larger than the sum of its proper divisors (462561471).

1278845889 is an equidigital number, since it uses as much as digits as its factorization.

1278845889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9069879.

The product of its digits is 10321920, while the sum is 60.

The square root of 1278845889 is about 35760.9548110785. The cubic root of 1278845889 is about 1085.4406215082.

The spelling of 1278845889 in words is "one billion, two hundred seventy-eight million, eight hundred forty-five thousand, eight hundred eighty-nine".