168121 has 4 divisors (see below), whose sum is σ = 170100. Its totient is φ = 166144.

The previous prime is 168109. The next prime is 168127. The reversal of 168121 is 121861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 121861 = 31 ⋅3931.

It can be written as a sum of positive squares in 2 ways, for example, as 55225 + 112896 = 235^2 + 336^2 .

It is a cyclic number.

It is not a de Polignac number, because 168121 - 2⁵ = 168089 is a prime.

It is a Duffinian number.

168121 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (168127) 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, 856 + ... + 1033.

It is an arithmetic number, because the mean of its divisors is an integer number (42525).

2¹⁶⁸¹²¹ is an apocalyptic number.

It is an amenable number.

168121 is a deficient number, since it is larger than the sum of its proper divisors (1979).

168121 is an equidigital number, since it uses as much as digits as its factorization.

168121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1978.

The product of its digits is 96, while the sum is 19.

The square root of 168121 is about 410.0256089563. The cubic root of 168121 is about 55.1917275638.

Adding to 168121 its reverse (121861), we get a palindrome (289982).

It can be divided in two parts, 168 and 121, that added together give a square (289 = 17²).

The spelling of 168121 in words is "one hundred sixty-eight thousand, one hundred twenty-one".