1281116840 has 16 divisors (see below), whose sum is σ = 2882512980. Its totient is φ = 512446720.

The previous prime is 1281116803. The next prime is 1281116843. The reversal of 1281116840 is 486111821.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1264940356 + 16176484 = 35566^2 + 4022^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1281116797 and 1281116806.

It is not an unprimeable number, because it can be changed into a prime (1281116843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16013921 + ... + 16014000.

Almost surely, 2^1281116840 is an apocalyptic number.

1281116840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1281116840 is an abundant number, since it is smaller than the sum of its proper divisors (1601396140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1281116840 is a wasteful number, since it uses less digits than its factorization.

1281116840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32027932 (or 32027928 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 32.

The square root of 1281116840 is about 35792.6925502958. The cubic root of 1281116840 is about 1086.0827433968.

The spelling of 1281116840 in words is "one billion, two hundred eighty-one million, one hundred sixteen thousand, eight hundred forty".