8128721701552 has 40 divisors (see below), whose sum is σ = 15762860755200. Its totient is φ = 4060887762240.

The previous prime is 8128721701549. The next prime is 8128721701559. The reversal of 8128721701552 is 2551071278218.

It is a happy number.

It is a super-2 number, since 2×8128721701552² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8128721701496 and 8128721701505.

It is not an unprimeable number, because it can be changed into a prime (8128721701559) 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, 132223173 + ... + 132284635.

It is an arithmetic number, because the mean of its divisors is an integer number (394071518880).

Almost surely, 2^{8128721701552} is an apocalyptic number.

It is an amenable number.

8128721701552 is a deficient number, since it is larger than the sum of its proper divisors (7634139053648).

8128721701552 is a wasteful number, since it uses less digits than its factorization.

8128721701552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68401 (or 68395 counting only the distinct ones).

The product of its (nonzero) digits is 627200, while the sum is 49.

The spelling of 8128721701552 in words is "eight trillion, one hundred twenty-eight billion, seven hundred twenty-one million, seven hundred one thousand, five hundred fifty-two".