12123557 has 2 divisors, whose sum is σ = 12123558. Its totient is φ = 12123556.

The previous prime is 12123523. The next prime is 12123563. The reversal of 12123557 is 75532121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6713281 + 5410276 = 2591^2 + 2326^2 .

It is a cyclic number.

It is not a de Polignac number, because 12123557 - 2⁶ = 12123493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12123257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6061778 + 6061779.

It is an arithmetic number, because the mean of its divisors is an integer number (6061779).

Almost surely, 2^12123557 is an apocalyptic number.

It is an amenable number.

12123557 is a deficient number, since it is larger than the sum of its proper divisors (1).

12123557 is an equidigital number, since it uses as much as digits as its factorization.

12123557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2100, while the sum is 26.

The square root of 12123557 is about 3481.8898604063. The cubic root of 12123557 is about 229.7259306359.

Adding to 12123557 its reverse (75532121), we get a palindrome (87655678).

The spelling of 12123557 in words is "twelve million, one hundred twenty-three thousand, five hundred fifty-seven".