71244821 has 2 divisors, whose sum is σ = 71244822. Its totient is φ = 71244820.

The previous prime is 71244787. The next prime is 71244827. The reversal of 71244821 is 12844217.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70980625 + 264196 = 8425^2 + 514^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71244821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71244827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35622410 + 35622411.

It is an arithmetic number, because the mean of its divisors is an integer number (35622411).

Almost surely, 2^71244821 is an apocalyptic number.

It is an amenable number.

71244821 is a deficient number, since it is larger than the sum of its proper divisors (1).

71244821 is an equidigital number, since it uses as much as digits as its factorization.

71244821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3584, while the sum is 29.

The square root of 71244821 is about 8440.6647250083. The cubic root of 71244821 is about 414.5571722006.

The spelling of 71244821 in words is "seventy-one million, two hundred forty-four thousand, eight hundred twenty-one".