18356660667666 has 48 divisors (see below), whose sum is σ = 40385395290240. Its totient is φ = 6024860190720.

The previous prime is 18356660667649. The next prime is 18356660667731. The reversal of 18356660667666 is 66676606665381.

It is a junction number, because it is equal to n+sod(n) for n = 18356660667594 and 18356660667603.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8356350 + ... + 10321913.

It is an arithmetic number, because the mean of its divisors is an integer number (841362401880).

Almost surely, 2^{18356660667666} is an apocalyptic number.

18356660667666 is an abundant number, since it is smaller than the sum of its proper divisors (22028734622574).

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

18356660667666 is a wasteful number, since it uses less digits than its factorization.

18356660667666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18679111 (or 18679108 counting only the distinct ones).

The product of its (nonzero) digits is 1410877440, while the sum is 72.

The spelling of 18356660667666 in words is "eighteen trillion, three hundred fifty-six billion, six hundred sixty million, six hundred sixty-seven thousand, six hundred sixty-six".