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BaseRepresentation
bin101110100111…
…101001011101
3211222220002102
4232213221131
511112033041
61113534445
7205606541
oct56475135
924886072
1012221021
11699791a
124114425
1326bb797
1418a1a21
15111609b
hexba7a5d

12221021 has 2 divisors, whose sum is σ = 12221022. Its totient is φ = 12221020.

The previous prime is 12220997. The next prime is 12221029. The reversal of 12221021 is 12012221.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6528025 + 5692996 = 2555^2 + 2386^2 .

It is a cyclic number.

It is not a de Polignac number, because 12221021 - 210 = 12219997 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 12220993 and 12221011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12221029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6110510 + 6110511.

It is an arithmetic number, because the mean of its divisors is an integer number (6110511).

Almost surely, 212221021 is an apocalyptic number.

It is an amenable number.

12221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

12221021 is an equidigital number, since it uses as much as digits as its factorization.

12221021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 12221021 is about 3495.8576916116. The cubic root of 12221021 is about 230.3398944314.

Adding to 12221021 its reverse (12012221), we get a palindrome (24233242).

The spelling of 12221021 in words is "twelve million, two hundred twenty-one thousand, twenty-one".