138930228 has 30 divisors (see below), whose sum is σ = 363191906. Its totient is φ = 46309968.

The previous prime is 138930199. The next prime is 138930241. The reversal of 138930228 is 822039831.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 92390544 + 46539684 = 9612^2 + 6822^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 138930192 and 138930201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 214075 + ... + 214722.

Almost surely, 2^138930228 is an apocalyptic number.

138930228 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

138930228 is an abundant number, since it is smaller than the sum of its proper divisors (224261678).

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

138930228 is a wasteful number, since it uses less digits than its factorization.

138930228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428813 (or 428802 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 138930228 is about 11786.8667592367. The cubic root of 138930228 is about 517.9234593208.

The spelling of 138930228 in words is "one hundred thirty-eight million, nine hundred thirty thousand, two hundred twenty-eight".