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121212281 is a prime number
BaseRepresentation
bin1110011100110…
…00110101111001
322110002012222202
413032120311321
5222012243111
620005555545
73001200401
oct716306571
9273065882
10121212281
116246a643
1234715bb5
131c15c958
1412153801
15a994b3b
hex7398d79

121212281 has 2 divisors, whose sum is σ = 121212282. Its totient is φ = 121212280.

The previous prime is 121212253. The next prime is 121212317. The reversal of 121212281 is 182212121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64722025 + 56490256 = 8045^2 + 7516^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-121212281 is a prime.

It is a super-2 number, since 2×1212122812 = 29384834130445922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (121212181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60606140 + 60606141.

It is an arithmetic number, because the mean of its divisors is an integer number (60606141).

Almost surely, 2121212281 is an apocalyptic number.

It is an amenable number.

121212281 is a deficient number, since it is larger than the sum of its proper divisors (1).

121212281 is an equidigital number, since it uses as much as digits as its factorization.

121212281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 128, while the sum is 20.

The square root of 121212281 is about 11009.6449079886. The cubic root of 121212281 is about 494.8978206261.

The spelling of 121212281 in words is "one hundred twenty-one million, two hundred twelve thousand, two hundred eighty-one".