71216720 has 40 divisors (see below), whose sum is σ = 166403040. Its totient is φ = 28344960.

The previous prime is 71216711. The next prime is 71216741. The reversal of 71216720 is 2761217.

It is a Cunningham number, because it is equal to 8439²-1.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 71216720.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14771 + ... + 18989.

It is an arithmetic number, because the mean of its divisors is an integer number (4160076).

Almost surely, 2^71216720 is an apocalyptic number.

It is an amenable number.

71216720 is an abundant number, since it is smaller than the sum of its proper divisors (95186320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71216720 is a wasteful number, since it uses less digits than its factorization.

71216720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4443 (or 4437 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 26.

The square root of 71216720 is about 8438.9999407513. Note that the first 4 decimals coincide. The cubic root of 71216720 is about 414.5026606216.

Adding to 71216720 its reverse (2761217), we get a palindrome (73977937).

The spelling of 71216720 in words is "seventy-one million, two hundred sixteen thousand, seven hundred twenty".