71521718640 has 160 divisors (see below), whose sum is σ = 242855081280. Its totient is φ = 17331535872.

The previous prime is 71521718633. The next prime is 71521718659. The reversal of 71521718640 is 4681712517.

It is a junction number, because it is equal to n+sod(n) for n = 71521718592 and 71521718601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 183919 + ... + 420558.

It is an arithmetic number, because the mean of its divisors is an integer number (1517844258).

Almost surely, 2^71521718640 is an apocalyptic number.

It is an amenable number.

71521718640 is an abundant number, since it is smaller than the sum of its proper divisors (171333362640).

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

71521718640 is a wasteful number, since it uses less digits than its factorization.

71521718640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 604539 (or 604533 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 42.

The spelling of 71521718640 in words is "seventy-one billion, five hundred twenty-one million, seven hundred eighteen thousand, six hundred forty".