1281856 has 14 divisors (see below), whose sum is σ = 2543810. Its totient is φ = 640896.

The previous prime is 1281853. The next prime is 1281871. The reversal of 1281856 is 6581821.

It can be written as a sum of positive squares in only one way, i.e., 968256 + 313600 = 984^2 + 560^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9951 + ... + 10078.

2^1281856 is an apocalyptic number.

1281856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1281856 is a deficient number, since it is larger than the sum of its proper divisors (1261954).

1281856 is an equidigital number, since it uses as much as digits as its factorization.

1281856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20041 (or 20031 counting only the distinct ones).

The product of its digits is 3840, while the sum is 31.

The square root of 1281856 is about 1132.1907966416. The cubic root of 1281856 is about 108.6291580601.

The spelling of 1281856 in words is "one million, two hundred eighty-one thousand, eight hundred fifty-six".