1291281 has 4 divisors (see below), whose sum is σ = 1721712. Its totient is φ = 860852.

The previous prime is 1291271. The next prime is 1291313. The reversal of 1291281 is 1821921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1821921 = 3 ⋅607307.

It is a cyclic number.

It is not a de Polignac number, because 1291281 - 2⁵ = 1291249 is a prime.

It is a super-2 number, since 2×1291281² = 3334813241922, which contains 22 as substring.

It is a D-number.

1291281 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1291211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215211 + ... + 215216.

It is an arithmetic number, because the mean of its divisors is an integer number (430428).

2^1291281 is an apocalyptic number.

It is an amenable number.

1291281 is a deficient number, since it is larger than the sum of its proper divisors (430431).

1291281 is an equidigital number, since it uses as much as digits as its factorization.

1291281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430430.

The product of its digits is 288, while the sum is 24.

The square root of 1291281 is about 1136.3454580364. The cubic root of 1291281 is about 108.8947445059.

The spelling of 1291281 in words is "one million, two hundred ninety-one thousand, two hundred eighty-one".