123312181 has 2 divisors, whose sum is σ = 123312182. Its totient is φ = 123312180.

The previous prime is 123312113. The next prime is 123312191. The reversal of 123312181 is 181213321.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95844100 + 27468081 = 9790^2 + 5241^2 .

It is a cyclic number.

It is not a de Polignac number, because 123312181 - 2⁷ = 123312053 is a prime.

It is a super-2 number, since 2×123312181² = 30411787965953522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123312191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61656090 + 61656091.

It is an arithmetic number, because the mean of its divisors is an integer number (61656091).

Almost surely, 2^123312181 is an apocalyptic number.

It is an amenable number.

123312181 is a deficient number, since it is larger than the sum of its proper divisors (1).

123312181 is an equidigital number, since it uses as much as digits as its factorization.

123312181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 22.

The square root of 123312181 is about 11104.6017938511. The cubic root of 123312181 is about 497.7393691669.

The spelling of 123312181 in words is "one hundred twenty-three million, three hundred twelve thousand, one hundred eighty-one".