71686397 has 2 divisors, whose sum is σ = 71686398. Its totient is φ = 71686396.

The previous prime is 71686393. The next prime is 71686403. The reversal of 71686397 is 79368617.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69572281 + 2114116 = 8341^2 + 1454^2 .

It is an emirp because it is prime and its reverse (79368617) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71686397 - 2² = 71686393 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71686393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35843198 + 35843199.

It is an arithmetic number, because the mean of its divisors is an integer number (35843199).

Almost surely, 2^71686397 is an apocalyptic number.

It is an amenable number.

71686397 is a deficient number, since it is larger than the sum of its proper divisors (1).

71686397 is an equidigital number, since it uses as much as digits as its factorization.

71686397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 381024, while the sum is 47.

The square root of 71686397 is about 8466.7819742804. The cubic root of 71686397 is about 415.4118850665.

The spelling of 71686397 in words is "seventy-one million, six hundred eighty-six thousand, three hundred ninety-seven".