18660221225716 has 12 divisors (see below), whose sum is σ = 37320442451488. Its totient is φ = 7997237668152.

The previous prime is 18660221225713. The next prime is 18660221225731. The reversal of 18660221225716 is 61752212206681.

18660221225716 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 18660221225716.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18660221225713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 333218236146 + ... + 333218236201.

Almost surely, 2^{18660221225716} is an apocalyptic number.

It is an amenable number.

18660221225716 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18660221225716 is a wasteful number, since it uses less digits than its factorization.

18660221225716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666436472358 (or 666436472356 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 49.

The spelling of 18660221225716 in words is "eighteen trillion, six hundred sixty billion, two hundred twenty-one million, two hundred twenty-five thousand, seven hundred sixteen".