66643163528 has 36 divisors (see below), whose sum is σ = 126282703365. Its totient is φ = 32971466208.

The previous prime is 66643163491. The next prime is 66643163551. The reversal of 66643163528 is 82536134666.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 48868407844 + 17774755684 = 221062^2 + 133322^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=182542.

It is a super-2 number, since 2×66643163528² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 78127550 + ... + 78128402.

Almost surely, 2^66643163528 is an apocalyptic number.

It is an amenable number.

66643163528 is a deficient number, since it is larger than the sum of its proper divisors (59639539837).

66643163528 is an frugal number, since it uses more digits than its factorization.

66643163528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1926 (or 962 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 50.

Multiplying 66643163528 by its sum of digits (50), we get a square (3332158176400 = 1825420²).

The spelling of 66643163528 in words is "sixty-six billion, six hundred forty-three million, one hundred sixty-three thousand, five hundred twenty-eight".