66646426660 has 48 divisors (see below), whose sum is σ = 152702948160. Its totient is φ = 24231565440.

The previous prime is 66646426607. The next prime is 66646426667. The reversal of 66646426660 is 6662464666.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 66646426598 and 66646426607.

It is not an unprimeable number, because it can be changed into a prime (66646426667) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1880827 + ... + 1915933.

It is an arithmetic number, because the mean of its divisors is an integer number (3181311420).

Almost surely, 2^66646426660 is an apocalyptic number.

It is an amenable number.

66646426660 is an abundant number, since it is smaller than the sum of its proper divisors (86056521500).

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

66646426660 is a wasteful number, since it uses less digits than its factorization.

66646426660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43756 (or 43754 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 52.

The spelling of 66646426660 in words is "sixty-six billion, six hundred forty-six million, four hundred twenty-six thousand, six hundred sixty".