217871966768 has 10 divisors (see below), whose sum is σ = 422126935644. Its totient is φ = 108935983376.

The previous prime is 217871966743. The next prime is 217871966771. The reversal of 217871966768 is 867669178712.

It is a junction number, because it is equal to n+sod(n) for n = 217871966698 and 217871966707.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 6808498946 + ... + 6808498977.

Almost surely, 2^217871966768 is an apocalyptic number.

It is an amenable number.

217871966768 is a deficient number, since it is larger than the sum of its proper divisors (204254968876).

217871966768 is a wasteful number, since it uses less digits than its factorization.

217871966768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13616997931 (or 13616997925 counting only the distinct ones).

The product of its digits is 85349376, while the sum is 68.

The spelling of 217871966768 in words is "two hundred seventeen billion, eight hundred seventy-one million, nine hundred sixty-six thousand, seven hundred sixty-eight".