71711721 has 24 divisors (see below), whose sum is σ = 105636960. Its totient is φ = 46870656.

The previous prime is 71711701. The next prime is 71711737. The reversal of 71711721 is 12711717.

It is not a de Polignac number, because 71711721 - 2¹⁰ = 71710697 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (71711701) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 108490 + ... + 109148.

It is an arithmetic number, because the mean of its divisors is an integer number (4401540).

Almost surely, 2^71711721 is an apocalyptic number.

It is an amenable number.

71711721 is a deficient number, since it is larger than the sum of its proper divisors (33925239).

71711721 is a wasteful number, since it uses less digits than its factorization.

71711721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 885 (or 882 counting only the distinct ones).

The product of its digits is 686, while the sum is 27.

The square root of 71711721 is about 8468.2773336730. The cubic root of 71711721 is about 415.4607955642.

The spelling of 71711721 in words is "seventy-one million, seven hundred eleven thousand, seven hundred twenty-one".