71304521 has 2 divisors, whose sum is σ = 71304522. Its totient is φ = 71304520.

The previous prime is 71304463. The next prime is 71304523. The reversal of 71304521 is 12540317.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58308496 + 12996025 = 7636^2 + 3605^2 .

It is an emirp because it is prime and its reverse (12540317) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71304521 - 2¹⁴ = 71288137 is a prime.

Together with 71304523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71304523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35652260 + 35652261.

It is an arithmetic number, because the mean of its divisors is an integer number (35652261).

Almost surely, 2^71304521 is an apocalyptic number.

It is an amenable number.

71304521 is a deficient number, since it is larger than the sum of its proper divisors (1).

71304521 is an equidigital number, since it uses as much as digits as its factorization.

71304521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 71304521 is about 8444.2004358021. The cubic root of 71304521 is about 414.6729333800.

Adding to 71304521 its reverse (12540317), we get a palindrome (83844838).

The spelling of 71304521 in words is "seventy-one million, three hundred four thousand, five hundred twenty-one".