66616555555050 has 96 divisors (see below), whose sum is σ = 168467010278400. Its totient is φ = 17415738202560.

The previous prime is 66616555555037. The next prime is 66616555555229. The reversal of 66616555555050 is 5055555561666.

It is a happy 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 47 ways as a sum of consecutive naturals, for example, 7007220 + ... + 13503119.

It is an arithmetic number, because the mean of its divisors is an integer number (1754864690400).

Almost surely, 2^{66616555555050} is an apocalyptic number.

66616555555050 is an abundant number, since it is smaller than the sum of its proper divisors (101850454723350).

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

66616555555050 is a wasteful number, since it uses less digits than its factorization.

66616555555050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20510780 (or 20510775 counting only the distinct ones).

The product of its (nonzero) digits is 101250000, while the sum is 60.

The spelling of 66616555555050 in words is "sixty-six trillion, six hundred sixteen billion, five hundred fifty-five million, five hundred fifty-five thousand, fifty".