66128212843 has 32 divisors (see below), whose sum is σ = 83999623680. Its totient is φ = 50561280000.

The previous prime is 66128212831. The next prime is 66128212859. The reversal of 66128212843 is 34821282166.

It is a happy number.

It is not a de Polignac number, because 66128212843 - 2²¹ = 66126115691 is a prime.

It is a super-2 number, since 2×66128212843² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 66128212843.

It is not an unprimeable number, because it can be changed into a prime (66128212873) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1951243 + ... + 1984843.

It is an arithmetic number, because the mean of its divisors is an integer number (2624988240).

Almost surely, 2^66128212843 is an apocalyptic number.

66128212843 is a deficient number, since it is larger than the sum of its proper divisors (17871410837).

66128212843 is a wasteful number, since it uses less digits than its factorization.

66128212843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34099.

The product of its digits is 221184, while the sum is 43.

The spelling of 66128212843 in words is "sixty-six billion, one hundred twenty-eight million, two hundred twelve thousand, eight hundred forty-three".