138209138 has 8 divisors (see below), whose sum is σ = 212135088. Its totient is φ = 67497444.

The previous prime is 138209131. The next prime is 138209153. The reversal of 138209138 is 831902831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 138209098 and 138209107.

It is not an unprimeable number, because it can be changed into a prime (138209131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 803456 + ... + 803627.

It is an arithmetic number, because the mean of its divisors is an integer number (26516886).

Almost surely, 2^138209138 is an apocalyptic number.

138209138 is a deficient number, since it is larger than the sum of its proper divisors (73925950).

138209138 is a wasteful number, since it uses less digits than its factorization.

138209138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1607128.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 138209138 is about 11756.2382588990. The cubic root of 138209138 is about 517.0258446401.

The spelling of 138209138 in words is "one hundred thirty-eight million, two hundred nine thousand, one hundred thirty-eight".