138319121 has 4 divisors (see below), whose sum is σ = 138348144. Its totient is φ = 138290100.

The previous prime is 138319087. The next prime is 138319163. The reversal of 138319121 is 121913831.

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: 121913831 = 13 ⋅9377987.

It is a cyclic number.

It is not a de Polignac number, because 138319121 - 2¹⁰ = 138318097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138312121) 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, 5495 + ... + 17516.

It is an arithmetic number, because the mean of its divisors is an integer number (34587036).

Almost surely, 2^138319121 is an apocalyptic number.

It is an amenable number.

138319121 is a deficient number, since it is larger than the sum of its proper divisors (29023).

138319121 is an equidigital number, since it uses as much as digits as its factorization.

138319121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29022.

The product of its digits is 1296, while the sum is 29.

The square root of 138319121 is about 11760.9149729092. The cubic root of 138319121 is about 517.1629532214.

The spelling of 138319121 in words is "one hundred thirty-eight million, three hundred nineteen thousand, one hundred twenty-one".