71391685 has 8 divisors (see below), whose sum is σ = 87985656. Its totient is φ = 55569600.

The previous prime is 71391641. The next prime is 71391713. The reversal of 71391685 is 58619317.

It can be written as a sum of positive squares in 4 ways, for example, as 6395841 + 64995844 = 2529^2 + 8062^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 71391685 - 2⁷ = 71391557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 192766 + ... + 193135.

It is an arithmetic number, because the mean of its divisors is an integer number (10998207).

Almost surely, 2^71391685 is an apocalyptic number.

It is an amenable number.

71391685 is a deficient number, since it is larger than the sum of its proper divisors (16593971).

71391685 is a wasteful number, since it uses less digits than its factorization.

71391685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385943.

The product of its digits is 45360, while the sum is 40.

The square root of 71391685 is about 8449.3600349376. The cubic root of 71391685 is about 414.8418325986.

The spelling of 71391685 in words is "seventy-one million, three hundred ninety-one thousand, six hundred eighty-five".