138658212 has 72 divisors (see below), whose sum is σ = 436992192. Its totient is φ = 36014400.

The previous prime is 138658211. The next prime is 138658231. The reversal of 138658212 is 212856831.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (138658211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22239 + ... + 27782.

It is an arithmetic number, because the mean of its divisors is an integer number (6069336).

Almost surely, 2^138658212 is an apocalyptic number.

138658212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

138658212 is an abundant number, since it is smaller than the sum of its proper divisors (298333980).

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

138658212 is a wasteful number, since it uses less digits than its factorization.

138658212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50049 (or 50044 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 138658212 is about 11775.3221611980. The cubic root of 138658212 is about 517.5852187602.

The spelling of 138658212 in words is "one hundred thirty-eight million, six hundred fifty-eight thousand, two hundred twelve".