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12421 has 2 divisors, whose sum is σ = 12422. Its totient is φ = 12420.

The previous prime is 12413. The next prime is 12433.

12421 is nontrivially palindromic in base 10.

It is the 46-th star number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12321 + 100 = 111^2 + 10^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 12421 - 23 = 12413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12398 and 12407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12401) 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, 6210 + 6211.

It is an arithmetic number, because the mean of its divisors is an integer number (6211).

212421 is an apocalyptic number.

It is an amenable number.

12421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12421 is an equidigital number, since it uses as much as digits as its factorization.

12421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16, while the sum is 10.

The square root of 12421 is about 111.4495401516. The cubic root of 12421 is about 23.1589494046.

The spelling of 12421 in words is "twelve thousand, four hundred twenty-one", and thus it is an iban number.