138189212 has 48 divisors (see below), whose sum is σ = 288153600. Its totient is φ = 57936816.

The previous prime is 138189211. The next prime is 138189283. The reversal of 138189212 is 212981831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138189211) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 63413 + ... + 65555.

It is an arithmetic number, because the mean of its divisors is an integer number (6003200).

Almost surely, 2^138189212 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 138189212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144076800).

138189212 is an abundant number, since it is smaller than the sum of its proper divisors (149964388).

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

138189212 is a wasteful number, since it uses less digits than its factorization.

138189212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2215 (or 2199 counting only the distinct ones).

The product of its digits is 6912, while the sum is 35.

The square root of 138189212 is about 11755.3907633902. The cubic root of 138189212 is about 517.0009964227. Note that the first 3 decimals are identical.

The spelling of 138189212 in words is "one hundred thirty-eight million, one hundred eighty-nine thousand, two hundred twelve".