71688447641 has 2 divisors, whose sum is σ = 71688447642. Its totient is φ = 71688447640.

The previous prime is 71688447631. The next prime is 71688447707. The reversal of 71688447641 is 14674488617.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67485648400 + 4202799241 = 259780^2 + 64829^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71688447641 is a prime.

It is not a weakly prime, because it can be changed into another prime (71688447631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35844223820 + 35844223821.

It is an arithmetic number, because the mean of its divisors is an integer number (35844223821).

Almost surely, 2^71688447641 is an apocalyptic number.

It is an amenable number.

71688447641 is a deficient number, since it is larger than the sum of its proper divisors (1).

71688447641 is an equidigital number, since it uses as much as digits as its factorization.

71688447641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7225344, while the sum is 56.

The spelling of 71688447641 in words is "seventy-one billion, six hundred eighty-eight million, four hundred forty-seven thousand, six hundred forty-one".