71785721472 has 64 divisors (see below), whose sum is σ = 194737910400. Its totient is φ = 23419449344.

The previous prime is 71785721471. The next prime is 71785721533. The reversal of 71785721472 is 27412758717.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (71785721471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1970697 + ... + 2006792.

It is an arithmetic number, because the mean of its divisors is an integer number (3042779850).

Almost surely, 2^71785721472 is an apocalyptic number.

It is an amenable number.

71785721472 is an abundant number, since it is smaller than the sum of its proper divisors (122952188928).

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

71785721472 is a wasteful number, since it uses less digits than its factorization.

71785721472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3977553 (or 3977541 counting only the distinct ones).

The product of its digits is 1536640, while the sum is 51.

The spelling of 71785721472 in words is "seventy-one billion, seven hundred eighty-five million, seven hundred twenty-one thousand, four hundred seventy-two".