138689149 has 4 divisors (see below), whose sum is σ = 144719136. Its totient is φ = 132659164.

The previous prime is 138689143. The next prime is 138689197. The reversal of 138689149 is 941986831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 941986831 = 47 ⋅20042273.

It is a cyclic number.

It is not a de Polignac number, because 138689149 - 2²⁵ = 105134717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138689143) 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 3 ways as a sum of consecutive naturals, for example, 3014959 + ... + 3015004.

It is an arithmetic number, because the mean of its divisors is an integer number (36179784).

Almost surely, 2^138689149 is an apocalyptic number.

It is an amenable number.

138689149 is a deficient number, since it is larger than the sum of its proper divisors (6029987).

138689149 is an equidigital number, since it uses as much as digits as its factorization.

138689149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6029986.

The product of its digits is 373248, while the sum is 49.

The square root of 138689149 is about 11776.6357250278. The cubic root of 138689149 is about 517.6237099127.

The spelling of 138689149 in words is "one hundred thirty-eight million, six hundred eighty-nine thousand, one hundred forty-nine".