2271721 has 2 divisors, whose sum is σ = 2271722. Its totient is φ = 2271720.

The previous prime is 2271683. The next prime is 2271743. The reversal of 2271721 is 1271722.

2271721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (2271743) can be obtained adding 2271721 to its sum of digits (22).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1525225 + 746496 = 1235^2 + 864^2 .

It is a cyclic number.

It is not a de Polignac number, because 2271721 - 2⁷ = 2271593 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 2271692 and 2271701.

It is not a weakly prime, because it can be changed into another prime (2271751) 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 as a sum of consecutive naturals, namely, 1135860 + 1135861.

It is an arithmetic number, because the mean of its divisors is an integer number (1135861).

2^2271721 is an apocalyptic number.

It is an amenable number.

2271721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2271721 is an equidigital number, since it uses as much as digits as its factorization.

2271721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 392, while the sum is 22.

The square root of 2271721 is about 1507.2229430313. Note that the first 3 decimals coincide. The cubic root of 2271721 is about 131.4573876301.

Subtracting from 2271721 its reverse (1271722), we obtain a palindrome (999999).

It can be divided in two parts, 2271 and 721, that added together give a palindrome (2992).

The spelling of 2271721 in words is "two million, two hundred seventy-one thousand, seven hundred twenty-one".