71512138722128 has 40 divisors (see below), whose sum is σ = 149219535645768. Its totient is φ = 33004118748672.

The previous prime is 71512138722067. The next prime is 71512138722187. The reversal of 71512138722128 is 82122783121517.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 13411035003664 + 58101103718464 = 3662108^2 + 7622408^2 .

It is a super-2 number, since 2×71512138722128² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3083051 + ... + 12350282.

Almost surely, 2^{71512138722128} is an apocalyptic number.

It is an amenable number.

71512138722128 is an abundant number, since it is smaller than the sum of its proper divisors (77707396923640).

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

71512138722128 is a wasteful number, since it uses less digits than its factorization.

71512138722128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15455631 (or 15455625 counting only the distinct ones).

The product of its digits is 752640, while the sum is 50.

The spelling of 71512138722128 in words is "seventy-one trillion, five hundred twelve billion, one hundred thirty-eight million, seven hundred twenty-two thousand, one hundred twenty-eight".