71656865 has 12 divisors (see below), whose sum is σ = 100027476. Its totient is φ = 49135968.

The previous prime is 71656859. The next prime is 71656867. The reversal of 71656865 is 56865617.

It can be written as a sum of positive squares in 2 ways, for example, as 19571776 + 52085089 = 4424^2 + 7217^2 .

It is not a de Polignac number, because 71656865 - 2⁶ = 71656801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71656867) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 145994 + ... + 146483.

It is an arithmetic number, because the mean of its divisors is an integer number (8335623).

Almost surely, 2^71656865 is an apocalyptic number.

It is an amenable number.

71656865 is a deficient number, since it is larger than the sum of its proper divisors (28370611).

71656865 is a wasteful number, since it uses less digits than its factorization.

71656865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292496 (or 292489 counting only the distinct ones).

The product of its digits is 302400, while the sum is 44.

The square root of 71656865 is about 8465.0378026327. The cubic root of 71656865 is about 415.3548327324.

The spelling of 71656865 in words is "seventy-one million, six hundred fifty-six thousand, eight hundred sixty-five".