18736228 has 36 divisors (see below), whose sum is σ = 38535420. Its totient is φ = 7947072.

The previous prime is 18736219. The next prime is 18736243. The reversal of 18736228 is 82263781.

It can be written as a sum of positive squares in 2 ways, for example, as 14500864 + 4235364 = 3808^2 + 2058^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20926 + ... + 21802.

Almost surely, 2^18736228 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 18736228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19267710).

18736228 is an abundant number, since it is smaller than the sum of its proper divisors (19799192).

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

18736228 is a wasteful number, since it uses less digits than its factorization.

18736228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004 (or 995 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 18736228 is about 4328.5364732205. The cubic root of 18736228 is about 265.5995822137.

The spelling of 18736228 in words is "eighteen million, seven hundred thirty-six thousand, two hundred twenty-eight".