1287798256 has 20 divisors (see below), whose sum is σ = 2529290992. Its totient is φ = 635078016.

The previous prime is 1287798143. The next prime is 1287798257. The reversal of 1287798256 is 6528977821.

It is a junction number, because it is equal to n+sod(n) for n = 1287798197 and 1287798206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287798257) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550116 + ... + 552451.

Almost surely, 2^1287798256 is an apocalyptic number.

1287798256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1287798256 is a deficient number, since it is larger than the sum of its proper divisors (1241492736).

1287798256 is a wasteful number, since it uses less digits than its factorization.

1287798256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1102648 (or 1102642 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 55.

The square root of 1287798256 is about 35885.9060913891. The cubic root of 1287798256 is about 1087.9675550806.

The spelling of 1287798256 in words is "one billion, two hundred eighty-seven million, seven hundred ninety-eight thousand, two hundred fifty-six".