12123989 has 4 divisors (see below), whose sum is σ = 12133440. Its totient is φ = 12114540.

The previous prime is 12123977. The next prime is 12124061. The reversal of 12123989 is 98932121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 98932121 = 43 ⋅2300747.

It is a cyclic number.

It is not a de Polignac number, because 12123989 - 2¹² = 12119893 is a prime.

It is a super-2 number, since 2×12123989² = 293982218544242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12123949) 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, 2429 + ... + 5490.

It is an arithmetic number, because the mean of its divisors is an integer number (3033360).

Almost surely, 2^12123989 is an apocalyptic number.

It is an amenable number.

12123989 is a deficient number, since it is larger than the sum of its proper divisors (9451).

12123989 is an equidigital number, since it uses as much as digits as its factorization.

12123989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9450.

The product of its digits is 7776, while the sum is 35.

The square root of 12123989 is about 3481.9518951301. The cubic root of 12123989 is about 229.7286592197.

The spelling of 12123989 in words is "twelve million, one hundred twenty-three thousand, nine hundred eighty-nine".