1281091 has 8 divisors (see below), whose sum is σ = 1473120. Its totient is φ = 1091328.

The previous prime is 1281089. The next prime is 1281097. The reversal of 1281091 is 1901821.

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

It is not a de Polignac number, because 1281091 - 2¹ = 1281089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1281097) 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, 915 + ... + 1843.

It is an arithmetic number, because the mean of its divisors is an integer number (184140).

2^1281091 is an apocalyptic number.

1281091 is a deficient number, since it is larger than the sum of its proper divisors (192029).

1281091 is an equidigital number, since it uses as much as digits as its factorization.

1281091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1133.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 1281091 is about 1131.8529056375. The cubic root of 1281091 is about 108.6075441287.

The spelling of 1281091 in words is "one million, two hundred eighty-one thousand, ninety-one".