18228672 has 224 divisors, whose sum is σ = 67299840. Its totient is φ = 4700160.

The previous prime is 18228671. The next prime is 18228677. The reversal of 18228672 is 27682281.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18228671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132988 + ... + 133124.

Almost surely, 2^18228672 is an apocalyptic number.

18228672 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18228672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33649920).

18228672 is an abundant number, since it is smaller than the sum of its proper divisors (49071168).

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

18228672 is a wasteful number, since it uses less digits than its factorization.

18228672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176 (or 160 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 18228672 is about 4269.5048893285. The cubic root of 18228672 is about 263.1792693151.

The spelling of 18228672 in words is "eighteen million, two hundred twenty-eight thousand, six hundred seventy-two".