138706121 has 8 divisors (see below), whose sum is σ = 143340288. Its totient is φ = 134082000.

The previous prime is 138706103. The next prime is 138706153. The reversal of 138706121 is 121607831.

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

It is a cyclic number.

It is not a de Polignac number, because 138706121 - 2¹⁰ = 138705097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138706181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34391 + ... + 38211.

It is an arithmetic number, because the mean of its divisors is an integer number (17917536).

Almost surely, 2^138706121 is an apocalyptic number.

It is an amenable number.

138706121 is a deficient number, since it is larger than the sum of its proper divisors (4634167).

138706121 is a wasteful number, since it uses less digits than its factorization.

138706121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5023.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 138706121 is about 11777.3562822902. The cubic root of 138706121 is about 517.6448236800.

It can be divided in two parts, 13870 and 6121, that added together give a palindrome (19991).

The spelling of 138706121 in words is "one hundred thirty-eight million, seven hundred six thousand, one hundred twenty-one".