1281155 has 8 divisors (see below), whose sum is σ = 1555200. Its totient is φ = 1013056.

The previous prime is 1281149. The next prime is 1281157. The reversal of 1281155 is 5511821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1281155 - 2¹⁰ = 1280131 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1281155.

It is not an unprimeable number, because it can be changed into a prime (1281157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 995 + ... + 1884.

It is an arithmetic number, because the mean of its divisors is an integer number (194400).

2^1281155 is an apocalyptic number.

1281155 is a deficient number, since it is larger than the sum of its proper divisors (274045).

1281155 is an equidigital number, since it uses as much as digits as its factorization.

1281155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2973.

The product of its digits is 400, while the sum is 23.

The square root of 1281155 is about 1131.8811775094. The cubic root of 1281155 is about 108.6093526828.

Adding to 1281155 its reverse (5511821), we get a palindrome (6792976).

The spelling of 1281155 in words is "one million, two hundred eighty-one thousand, one hundred fifty-five".