228509440 has 72 divisors (see below), whose sum is σ = 551144160. Its totient is φ = 90771456.

The previous prime is 228509389. The next prime is 228509459. The reversal of 228509440 is 44905822.

It is a super-2 number, since 2×228509440² = 104433128338227200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 228509396 and 228509405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 213226 + ... + 214294.

It is an arithmetic number, because the mean of its divisors is an integer number (7654780).

Almost surely, 2^228509440 is an apocalyptic number.

228509440 is a gapful number since it is divisible by the number (20) 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 228509440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (275572080).

228509440 is an abundant number, since it is smaller than the sum of its proper divisors (322634720).

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

228509440 is a wasteful number, since it uses less digits than its factorization.

228509440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1257 (or 1243 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 228509440 is about 15116.5287020533. The cubic root of 228509440 is about 611.3661399722.

The spelling of 228509440 in words is "two hundred twenty-eight million, five hundred nine thousand, four hundred forty".