71006665 has 4 divisors (see below), whose sum is σ = 85208004. Its totient is φ = 56805328.

The previous prime is 71006659. The next prime is 71006669. The reversal of 71006665 is 56660017.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56660017 = 23 ⋅2463479.

It can be written as a sum of positive squares in 2 ways, for example, as 39601849 + 31404816 = 6293^2 + 5604^2 .

It is a cyclic number.

It is not a de Polignac number, because 71006665 - 2⁹ = 71006153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71006669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7100662 + ... + 7100671.

It is an arithmetic number, because the mean of its divisors is an integer number (21302001).

Almost surely, 2^71006665 is an apocalyptic number.

It is an amenable number.

71006665 is a deficient number, since it is larger than the sum of its proper divisors (14201339).

71006665 is a wasteful number, since it uses less digits than its factorization.

71006665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14201338.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 71006665 is about 8426.5452588828. The cubic root of 71006665 is about 414.0947316027.

The spelling of 71006665 in words is "seventy-one million, six thousand, six hundred sixty-five".