71145517 has 2 divisors, whose sum is σ = 71145518. Its totient is φ = 71145516.

The previous prime is 71145469. The next prime is 71145533. The reversal of 71145517 is 71554117.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63904036 + 7241481 = 7994^2 + 2691^2 .

It is an emirp because it is prime and its reverse (71554117) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71145517 - 2¹⁵ = 71112749 is a prime.

It is equal to p_4181458 and since 71145517 and 4181458 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71145577) 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, 35572758 + 35572759.

It is an arithmetic number, because the mean of its divisors is an integer number (35572759).

Almost surely, 2^71145517 is an apocalyptic number.

It is an amenable number.

71145517 is a deficient number, since it is larger than the sum of its proper divisors (1).

71145517 is an equidigital number, since it uses as much as digits as its factorization.

71145517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4900, while the sum is 31.

The square root of 71145517 is about 8434.7801986774. The cubic root of 71145517 is about 414.3644736226.

The spelling of 71145517 in words is "seventy-one million, one hundred forty-five thousand, five hundred seventeen".