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71238281 is a prime number
BaseRepresentation
bin1000011111100…
…00001010001001
311222001021112212
410033300022021
5121214111111
611022514505
71523341532
oct417601211
9158037485
1071238281
1137237414
121ba35a35
13119b333a
149665689
1563c298b
hex43f0289

71238281 has 2 divisors, whose sum is σ = 71238282. Its totient is φ = 71238280.

The previous prime is 71238269. The next prime is 71238287. The reversal of 71238281 is 18283217.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64561225 + 6677056 = 8035^2 + 2584^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-71238281 is a prime.

It is a super-2 number, since 2×712382812 = 10149785359669922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71238287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35619140 + 35619141.

It is an arithmetic number, because the mean of its divisors is an integer number (35619141).

Almost surely, 271238281 is an apocalyptic number.

It is an amenable number.

71238281 is a deficient number, since it is larger than the sum of its proper divisors (1).

71238281 is an equidigital number, since it uses as much as digits as its factorization.

71238281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 32.

The square root of 71238281 is about 8440.2773058709. The cubic root of 71238281 is about 414.5444868955.

The spelling of 71238281 in words is "seventy-one million, two hundred thirty-eight thousand, two hundred eighty-one".