71643617 has 2 divisors, whose sum is σ = 71643618. Its totient is φ = 71643616.

The previous prime is 71643589. The next prime is 71643619. The reversal of 71643617 is 71634617.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54037201 + 17606416 = 7351^2 + 4196^2 .

It is a cyclic number.

It is not a de Polignac number, because 71643617 - 2⁸ = 71643361 is a prime.

Together with 71643619, 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 (71643619) 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, 35821808 + 35821809.

It is an arithmetic number, because the mean of its divisors is an integer number (35821809).

Almost surely, 2^71643617 is an apocalyptic number.

It is an amenable number.

71643617 is a deficient number, since it is larger than the sum of its proper divisors (1).

71643617 is an equidigital number, since it uses as much as digits as its factorization.

71643617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 35.

The square root of 71643617 is about 8464.2552537125. The cubic root of 71643617 is about 415.3292340687.

The spelling of 71643617 in words is "seventy-one million, six hundred forty-three thousand, six hundred seventeen".