123012121 has 6 divisors (see below), whose sum is σ = 125941290. Its totient is φ = 120149568.

The previous prime is 123012107. The next prime is 123012143. The reversal of 123012121 is 121210321.

It can be written as a sum of positive squares in only one way, i.e., 117418896 + 5593225 = 10836^2 + 2365^2 .

It is not a de Polignac number, because 123012121 - 2⁵ = 123012089 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123018121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 31416 + ... + 35113.

It is an arithmetic number, because the mean of its divisors is an integer number (20990215).

Almost surely, 2^123012121 is an apocalyptic number.

It is an amenable number.

123012121 is a deficient number, since it is larger than the sum of its proper divisors (2929169).

123012121 is an frugal number, since it uses more digits than its factorization.

123012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66615 (or 66572 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 123012121 is about 11091.0829498296. The cubic root of 123012121 is about 497.3353188428.

Adding to 123012121 its reverse (121210321), we get a palindrome (244222442).

The spelling of 123012121 in words is "one hundred twenty-three million, twelve thousand, one hundred twenty-one".