4421 has 2 divisors, whose sum is σ = 4422.
Its totient is φ = 4420.
The previous prime is 4409. The next prime is 4423. The reversal of 4421 is 1244.
Adding to 4421 its reverse (1244), we get a palindrome (5665).
It is an alternating factorial (4421 = 7! - 6! + 5! - 4! + 3! - 2! + 1!).
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 4225 + 196 = 65^2 + 14^2
It is a cyclic number.
It is not a de Polignac number, because 4421 - 26 = 4357 is a prime.
Together with 4423, it forms a pair of twin primes.
It is a Chen prime.
It is a plaindrome in base 11, base 15 and base 16.
It is a nialpdrome in base 10.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (4423) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2210 + 2211.
It is an arithmetic number, because the mean of its divisors is an integer number (2211).
24421 is an apocalyptic number.
It is an amenable number.
4421 is a deficient number, since it is larger than the sum of its proper divisors (1).
4421 is an equidigital number, since it uses as much as digits as its factorization.
4421 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 32, while the sum is 11.
The square root of 4421 is about 66.4906008395.
The cubic root of 4421 is about 16.4124533609.
The spelling of 4421 in words is "four thousand, four hundred twenty-one", and thus it is an iban number.