12689121 has 4 divisors (see below), whose sum is σ = 16918832. Its totient is φ = 8459412.

The previous prime is 12689099. The next prime is 12689129. The reversal of 12689121 is 12198621.

It is a happy number.

12689121 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

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.

It is not a de Polignac number, because 12689121 - 2⁶ = 12689057 is a prime.

It is a super-2 number, since 2×12689121² = 322027583505282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12689129) 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, 2114851 + ... + 2114856.

It is an arithmetic number, because the mean of its divisors is an integer number (4229708).

Almost surely, 2^12689121 is an apocalyptic number.

It is an amenable number.

12689121 is a deficient number, since it is larger than the sum of its proper divisors (4229711).

12689121 is an equidigital number, since it uses as much as digits as its factorization.

12689121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4229710.

The product of its digits is 1728, while the sum is 30.

The square root of 12689121 is about 3562.1792487184. The cubic root of 12689121 is about 233.2440172896.

The spelling of 12689121 in words is "twelve million, six hundred eighty-nine thousand, one hundred twenty-one".