71996309 has 16 divisors (see below), whose sum is σ = 95043456. Its totient is φ = 52800000.

The previous prime is 71996297. The next prime is 71996317. The reversal of 71996309 is 90369917.

It is a happy number.

It is not a de Polignac number, because 71996309 - 2⁴ = 71996293 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71996309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71996359) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26192 + ... + 28809.

It is an arithmetic number, because the mean of its divisors is an integer number (5940216).

Almost surely, 2^71996309 is an apocalyptic number.

It is an amenable number.

71996309 is a deficient number, since it is larger than the sum of its proper divisors (23047147).

71996309 is a wasteful number, since it uses less digits than its factorization.

71996309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55036.

The product of its (nonzero) digits is 91854, while the sum is 44.

The square root of 71996309 is about 8485.0638771903. The cubic root of 71996309 is about 416.0096556098.

The spelling of 71996309 in words is "seventy-one million, nine hundred ninety-six thousand, three hundred nine".