2821281 has 8 divisors (see below), whose sum is σ = 3780384. Its totient is φ = 1871520.

The previous prime is 2821277. The next prime is 2821289. The reversal of 2821281 is 1821282.

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

It is not a de Polignac number, because 2821281 - 2² = 2821277 is a prime.

It is a super-2 number, since 2×2821281² = 15919252961922, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (2821289) 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, 1596 + ... + 2861.

It is an arithmetic number, because the mean of its divisors is an integer number (472548).

2^2821281 is an apocalyptic number.

It is an amenable number.

2821281 is a deficient number, since it is larger than the sum of its proper divisors (959103).

2821281 is a wasteful number, since it uses less digits than its factorization.

2821281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4671.

The product of its digits is 512, while the sum is 24.

The square root of 2821281 is about 1679.6669312694. Note that the first 3 decimals coincide. The cubic root of 2821281 is about 141.3021537119.

Subtracting from 2821281 its reverse (1821282), we obtain a palindrome (999999).

The spelling of 2821281 in words is "two million, eight hundred twenty-one thousand, two hundred eighty-one".