1281855 has 16 divisors (see below), whose sum is σ = 2074464. Its totient is φ = 675840.

The previous prime is 1281853. The next prime is 1281871. The reversal of 1281855 is 5581821.

It is not a de Polignac number, because 1281855 - 2¹ = 1281853 is a prime.

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 in 15 ways as a sum of consecutive naturals, for example, 1015 + ... + 1895.

It is an arithmetic number, because the mean of its divisors is an integer number (129654).

2^1281855 is an apocalyptic number.

1281855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1281855 is a deficient number, since it is larger than the sum of its proper divisors (792609).

1281855 is an equidigital number, since it uses as much as digits as its factorization.

1281855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 986.

The product of its digits is 3200, while the sum is 30.

The square root of 1281855 is about 1132.1903550199. The cubic root of 1281855 is about 108.6291298122.

The spelling of 1281855 in words is "one million, two hundred eighty-one thousand, eight hundred fifty-five".