228531618 has 80 divisors (see below), whose sum is σ = 589906944. Its totient is φ = 64774080.

The previous prime is 228531617. The next prime is 228531631. The reversal of 228531618 is 816135822.

It is a happy number.

228531618 is a `hidden beast` number, since 2 + 2 + 8 + 5 + 31 + 618 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (228531617) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 154623 + ... + 156093.

Almost surely, 2^228531618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 228531618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294953472).

228531618 is an abundant number, since it is smaller than the sum of its proper divisors (361375326).

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

228531618 is a wasteful number, since it uses less digits than its factorization.

228531618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1629 (or 1620 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 228531618 is about 15117.2622521408. The cubic root of 228531618 is about 611.3859180605.

The spelling of 228531618 in words is "two hundred twenty-eight million, five hundred thirty-one thousand, six hundred eighteen".