138117121 has 4 divisors (see below), whose sum is σ = 142572544. Its totient is φ = 133661700.

The previous prime is 138117101. The next prime is 138117127. The reversal of 138117121 is 121711831.

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: 121711831 = 2017 ⋅60343.

It is a cyclic number.

It is not a de Polignac number, because 138117121 - 2¹⁷ = 137986049 is a prime.

It is a super-2 number, since 2×138117121² = 38152678226657282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138117127) 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, 2227665 + ... + 2227726.

It is an arithmetic number, because the mean of its divisors is an integer number (35643136).

It is a Proth number, since it is equal to 4215 ⋅ 2¹⁵ + 1 and 4215 < 2¹⁵.

Almost surely, 2^138117121 is an apocalyptic number.

It is an amenable number.

138117121 is a deficient number, since it is larger than the sum of its proper divisors (4455423).

138117121 is an equidigital number, since it uses as much as digits as its factorization.

138117121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4455422.

The product of its digits is 336, while the sum is 25.

The square root of 138117121 is about 11752.3240680301. The cubic root of 138117121 is about 516.9110771943.

Adding to 138117121 its reverse (121711831), we get a palindrome (259828952).

The spelling of 138117121 in words is "one hundred thirty-eight million, one hundred seventeen thousand, one hundred twenty-one".