138396212 has 6 divisors (see below), whose sum is σ = 242193378. Its totient is φ = 69198104.

The previous prime is 138396211. The next prime is 138396217. The reversal of 138396212 is 212693831.

It can be written as a sum of positive squares in only one way, i.e., 130965136 + 7431076 = 11444^2 + 2726^2 .

It is a super-2 number, since 2×138396212² = 38307022991897888, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138396211) 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 as a sum of consecutive naturals, namely, 17299523 + ... + 17299530.

It is an arithmetic number, because the mean of its divisors is an integer number (40365563).

Almost surely, 2^138396212 is an apocalyptic number.

It is an amenable number.

138396212 is a deficient number, since it is larger than the sum of its proper divisors (103797166).

138396212 is a wasteful number, since it uses less digits than its factorization.

138396212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34599057 (or 34599055 counting only the distinct ones).

The product of its digits is 15552, while the sum is 35.

The square root of 138396212 is about 11764.1919399507. The cubic root of 138396212 is about 517.2590141864.

The spelling of 138396212 in words is "one hundred thirty-eight million, three hundred ninety-six thousand, two hundred twelve".