228138240 has 216 divisors, whose sum is σ = 802507104. Its totient is φ = 55193600.

The previous prime is 228138233. The next prime is 228138241. The reversal of 228138240 is 42831822.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 228138198 and 228138207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228138241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 464395 + ... + 464885.

Almost surely, 2^228138240 is an apocalyptic number.

228138240 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 228138240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401253552).

228138240 is an abundant number, since it is smaller than the sum of its proper divisors (574368864).

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

228138240 is a wasteful number, since it uses less digits than its factorization.

228138240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 512 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 228138240 is about 15104.2457607124. The cubic root of 228138240 is about 611.0349179080.

The spelling of 228138240 in words is "two hundred twenty-eight million, one hundred thirty-eight thousand, two hundred forty".