66506665516 has 24 divisors (see below), whose sum is σ = 116660083680. Its totient is φ = 33175296000.

The previous prime is 66506665487. The next prime is 66506665531. The reversal of 66506665516 is 61556660566.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3546966 + ... + 3565666.

It is an arithmetic number, because the mean of its divisors is an integer number (4860836820).

Almost surely, 2^66506665516 is an apocalyptic number.

It is an amenable number.

66506665516 is a deficient number, since it is larger than the sum of its proper divisors (50153418164).

66506665516 is a wasteful number, since it uses less digits than its factorization.

66506665516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20745 (or 20743 counting only the distinct ones).

The product of its (nonzero) digits is 5832000, while the sum is 52.

The spelling of 66506665516 in words is "sixty-six billion, five hundred six million, six hundred sixty-five thousand, five hundred sixteen".