2841721 has 4 divisors (see below), whose sum is σ = 2848500. Its totient is φ = 2834944.

The previous prime is 2841691. The next prime is 2841733. The reversal of 2841721 is 1271482.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1960000 + 881721 = 1400^2 + 939^2 .

It is a cyclic number.

It is not a de Polignac number, because 2841721 - 2⁷ = 2841593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2841781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2716 + ... + 3613.

It is an arithmetic number, because the mean of its divisors is an integer number (712125).

2^2841721 is an apocalyptic number.

It is an amenable number.

2841721 is a deficient number, since it is larger than the sum of its proper divisors (6779).

2841721 is an equidigital number, since it uses as much as digits as its factorization.

2841721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6778.

The product of its digits is 896, while the sum is 25.

The square root of 2841721 is about 1685.7404901111. The cubic root of 2841721 is about 141.6425746036.

The spelling of 2841721 in words is "two million, eight hundred forty-one thousand, seven hundred twenty-one".