1279198989 has 12 divisors (see below), whose sum is σ = 1850613856. Its totient is φ = 851469192.

The previous prime is 1279198951. The next prime is 1279198993. The reversal of 1279198989 is 9898919721.

It is not a de Polignac number, because 1279198989 - 2⁸ = 1279198733 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1279198909) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 104737 + ... + 116310.

Almost surely, 2^1279198989 is an apocalyptic number.

It is an amenable number.

1279198989 is a deficient number, since it is larger than the sum of its proper divisors (571414867).

1279198989 is a wasteful number, since it uses less digits than its factorization.

1279198989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221696 (or 221693 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 63.

The square root of 1279198989 is about 35765.8914190601. The cubic root of 1279198989 is about 1085.5405120469.

The spelling of 1279198989 in words is "one billion, two hundred seventy-nine million, one hundred ninety-eight thousand, nine hundred eighty-nine".