2811281 has 4 divisors (see below), whose sum is σ = 3066864. Its totient is φ = 2555700.

The previous prime is 2811269. The next prime is 2811283. The reversal of 2811281 is 1821182.

It is a happy number.

2811281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 2811281 - 2⁶ = 2811217 is a prime.

It is a super-2 number, since 2×2811281² = 15806601721922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2811283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127775 + ... + 127796.

It is an arithmetic number, because the mean of its divisors is an integer number (766716).

2^2811281 is an apocalyptic number.

It is an amenable number.

2811281 is a deficient number, since it is larger than the sum of its proper divisors (255583).

2811281 is a wasteful number, since it uses less digits than its factorization.

2811281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255582.

The product of its digits is 256, while the sum is 23.

The square root of 2811281 is about 1676.6875081541. The cubic root of 2811281 is about 141.1350080888.

Subtracting from 2811281 its reverse (1821182), we obtain a palindrome (990099).

The spelling of 2811281 in words is "two million, eight hundred eleven thousand, two hundred eighty-one".