66001166656606 has 4 divisors (see below), whose sum is σ = 99001749984912. Its totient is φ = 33000583328302.

The previous prime is 66001166656589. The next prime is 66001166656643. The reversal of 66001166656606 is 60665666110066.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16500291664150 + ... + 16500291664153.

It is an arithmetic number, because the mean of its divisors is an integer number (24750437496228).

Almost surely, 2^{66001166656606} is an apocalyptic number.

66001166656606 is a deficient number, since it is larger than the sum of its proper divisors (33000583328306).

66001166656606 is a wasteful number, since it uses less digits than its factorization.

66001166656606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33000583328305.

The product of its (nonzero) digits is 8398080, while the sum is 55.

The spelling of 66001166656606 in words is "sixty-six trillion, one billion, one hundred sixty-six million, six hundred fifty-six thousand, six hundred six".