71605168637 has 2 divisors, whose sum is σ = 71605168638. Its totient is φ = 71605168636.

The previous prime is 71605168589. The next prime is 71605168639. The reversal of 71605168637 is 73686150617.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71427373081 + 177795556 = 267259^2 + 13334^2 .

It is a cyclic number.

It is not a de Polignac number, because 71605168637 - 2⁶ = 71605168573 is a prime.

Together with 71605168639, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71605168639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35802584318 + 35802584319.

It is an arithmetic number, because the mean of its divisors is an integer number (35802584319).

Almost surely, 2^71605168637 is an apocalyptic number.

It is an amenable number.

71605168637 is a deficient number, since it is larger than the sum of its proper divisors (1).

71605168637 is an equidigital number, since it uses as much as digits as its factorization.

71605168637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1270080, while the sum is 50.

The spelling of 71605168637 in words is "seventy-one billion, six hundred five million, one hundred sixty-eight thousand, six hundred thirty-seven".