18221076 has 72 divisors (see below), whose sum is σ = 51367680. Its totient is φ = 5412096.

The previous prime is 18221041. The next prime is 18221081. The reversal of 18221076 is 67012281.

It is a super-2 number, since 2×18221076² = 664015221195552, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10845 + ... + 12411.

It is an arithmetic number, because the mean of its divisors is an integer number (713440).

Almost surely, 2^18221076 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18221076, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25683840).

18221076 is an abundant number, since it is smaller than the sum of its proper divisors (33146604).

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

18221076 is a wasteful number, since it uses less digits than its factorization.

18221076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1613 (or 1608 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 18221076 is about 4268.6152321333. The cubic root of 18221076 is about 263.1427080948.

The spelling of 18221076 in words is "eighteen million, two hundred twenty-one thousand, seventy-six".