9421 has 2 divisors, whose sum is σ = 9422.
Its totient is φ = 9420.
The previous prime is 9419. The next prime is 9431. The reversal of 9421 is 1249.
9421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 7396 + 2025 = 86^2 + 45^2
It is an emirp because it is prime and its reverse (1249) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 9421 - 21 = 9419 is a prime.
Together with 9419, it forms a pair of twin primes.
9421 is a lucky number.
It is a plaindrome in base 16.
It is a nialpdrome in base 10 and base 12.
It is a junction number, because it is equal to n+sod(n) for n = 9395 and 9404.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (9431) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4710 + 4711.
It is an arithmetic number, because the mean of its divisors is an integer number (4711).
29421 is an apocalyptic number.
It is an amenable number.
9421 is a deficient number, since it is larger than the sum of its proper divisors (1).
9421 is an equidigital number, since it uses as much as digits as its factorization.
9421 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 72, while the sum is 16.
The square root of 9421 is about 97.0618359604.
The cubic root of 9421 is about 21.1202474049.
The spelling of 9421 in words is "nine thousand, four hundred twenty-one".