66938228668 has 6 divisors (see below), whose sum is σ = 117141900176. Its totient is φ = 33469114332.

The previous prime is 66938228629. The next prime is 66938228677. The reversal of 66938228668 is 86682283966.

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, 8367278580 + ... + 8367278587.

Almost surely, 2^66938228668 is an apocalyptic number.

It is an amenable number.

66938228668 is a deficient number, since it is larger than the sum of its proper divisors (50203671508).

66938228668 is a wasteful number, since it uses less digits than its factorization.

66938228668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16734557171 (or 16734557169 counting only the distinct ones).

The product of its digits is 71663616, while the sum is 64.

The spelling of 66938228668 in words is "sixty-six billion, nine hundred thirty-eight million, two hundred twenty-eight thousand, six hundred sixty-eight".