121236161 has 4 divisors (see below), whose sum is σ = 124512852. Its totient is φ = 117959472.

The previous prime is 121236149. The next prime is 121236187. The reversal of 121236161 is 161632121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 48219136 + 73017025 = 6944^2 + 8545^2 .

It is a cyclic number.

It is not a de Polignac number, because 121236161 - 2¹⁸ = 120974017 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (121266161) 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, 1638290 + ... + 1638363.

It is an arithmetic number, because the mean of its divisors is an integer number (31128213).

Almost surely, 2^121236161 is an apocalyptic number.

It is an amenable number.

121236161 is a deficient number, since it is larger than the sum of its proper divisors (3276691).

121236161 is an equidigital number, since it uses as much as digits as its factorization.

121236161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3276690.

The product of its digits is 432, while the sum is 23.

The square root of 121236161 is about 11010.7293582215. The cubic root of 121236161 is about 494.9303183891.

Adding to 121236161 its reverse (161632121), we get a palindrome (282868282).

It can be divided in two parts, 1212 and 36161, that added together give a palindrome (37373).

The spelling of 121236161 in words is "one hundred twenty-one million, two hundred thirty-six thousand, one hundred sixty-one".