18221366 has 8 divisors (see below), whose sum is σ = 28213824. Its totient is φ = 8816760.

The previous prime is 18221341. The next prime is 18221389. The reversal of 18221366 is 66312281.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146885 + ... + 147008.

It is an arithmetic number, because the mean of its divisors is an integer number (3526728).

Almost surely, 2^18221366 is an apocalyptic number.

18221366 is a deficient number, since it is larger than the sum of its proper divisors (9992458).

18221366 is a wasteful number, since it uses less digits than its factorization.

18221366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293926.

The product of its digits is 3456, while the sum is 29.

The square root of 18221366 is about 4268.6492008597. The cubic root of 18221366 is about 263.1441041152.

The spelling of 18221366 in words is "eighteen million, two hundred twenty-one thousand, three hundred sixty-six".