123131232121 has 2 divisors, whose sum is σ = 123131232122. Its totient is φ = 123131232120.

The previous prime is 123131232071. The next prime is 123131232131. The reversal of 123131232121 is 121232131321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 109849822096 + 13281410025 = 331436^2 + 115245^2 .

It is a cyclic number.

It is not a de Polignac number, because 123131232121 - 2¹¹ = 123131230073 is a prime.

It is a super-2 number, since 2×123131232121² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 123131232092 and 123131232101.

It is not a weakly prime, because it can be changed into another prime (123131232131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61565616060 + 61565616061.

It is an arithmetic number, because the mean of its divisors is an integer number (61565616061).

Almost surely, 2^123131232121 is an apocalyptic number.

It is an amenable number.

123131232121 is a deficient number, since it is larger than the sum of its proper divisors (1).

123131232121 is an equidigital number, since it uses as much as digits as its factorization.

123131232121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 22.

Adding to 123131232121 its reverse (121232131321), we get a palindrome (244363363442).

The spelling of 123131232121 in words is "one hundred twenty-three billion, one hundred thirty-one million, two hundred thirty-two thousand, one hundred twenty-one".