12158989 has 2 divisors, whose sum is σ = 12158990. Its totient is φ = 12158988.

The previous prime is 12158987. The next prime is 12158999. The reversal of 12158989 is 98985121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11168964 + 990025 = 3342^2 + 995^2 .

It is an emirp because it is prime and its reverse (98985121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12158989 - 2¹ = 12158987 is a prime.

Together with 12158987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12158987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6079494 + 6079495.

It is an arithmetic number, because the mean of its divisors is an integer number (6079495).

Almost surely, 2^12158989 is an apocalyptic number.

It is an amenable number.

12158989 is a deficient number, since it is larger than the sum of its proper divisors (1).

12158989 is an equidigital number, since it uses as much as digits as its factorization.

12158989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 43.

The square root of 12158989 is about 3486.9741897525. The cubic root of 12158989 is about 229.9495100262.

The spelling of 12158989 in words is "twelve million, one hundred fifty-eight thousand, nine hundred eighty-nine".