12218989 has 2 divisors, whose sum is σ = 12218990. Its totient is φ = 12218988.

The previous prime is 12218981. The next prime is 12219007. The reversal of 12218989 is 98981221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6734025 + 5484964 = 2595^2 + 2342^2 .

It is a cyclic number.

It is not a de Polignac number, because 12218989 - 2³ = 12218981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12218981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6109494 + 6109495.

It is an arithmetic number, because the mean of its divisors is an integer number (6109495).

Almost surely, 2^12218989 is an apocalyptic number.

It is an amenable number.

12218989 is a deficient number, since it is larger than the sum of its proper divisors (1).

12218989 is an equidigital number, since it uses as much as digits as its factorization.

12218989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 40.

The square root of 12218989 is about 3495.5670498504. The cubic root of 12218989 is about 230.3271274509.

The spelling of 12218989 in words is "twelve million, two hundred eighteen thousand, nine hundred eighty-nine".