71316521 has 2 divisors, whose sum is σ = 71316522. Its totient is φ = 71316520.

The previous prime is 71316467. The next prime is 71316527. The reversal of 71316521 is 12561317.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59892121 + 11424400 = 7739^2 + 3380^2 .

It is a cyclic number.

It is not a de Polignac number, because 71316521 - 2¹⁸ = 71054377 is a prime.

It is not a weakly prime, because it can be changed into another prime (71316527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35658260 + 35658261.

It is an arithmetic number, because the mean of its divisors is an integer number (35658261).

Almost surely, 2^71316521 is an apocalyptic number.

It is an amenable number.

71316521 is a deficient number, since it is larger than the sum of its proper divisors (1).

71316521 is an equidigital number, since it uses as much as digits as its factorization.

71316521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1260, while the sum is 26.

The square root of 71316521 is about 8444.9109527573. The cubic root of 71316521 is about 414.6961941589.

Adding to 71316521 its reverse (12561317), we get a palindrome (83877838).

The spelling of 71316521 in words is "seventy-one million, three hundred sixteen thousand, five hundred twenty-one".