12185981 has 2 divisors, whose sum is σ = 12185982. Its totient is φ = 12185980.

The previous prime is 12185959. The next prime is 12186001. The reversal of 12185981 is 18958121.

12185981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10956100 + 1229881 = 3310^2 + 1109^2 .

It is a cyclic number.

It is not a de Polignac number, because 12185981 - 2⁶ = 12185917 is a prime.

It is a super-2 number, since 2×12185981² = 296996265864722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12185941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6092990 + 6092991.

It is an arithmetic number, because the mean of its divisors is an integer number (6092991).

Almost surely, 2^12185981 is an apocalyptic number.

It is an amenable number.

12185981 is a deficient number, since it is larger than the sum of its proper divisors (1).

12185981 is an equidigital number, since it uses as much as digits as its factorization.

12185981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 35.

The square root of 12185981 is about 3490.8424484643. The cubic root of 12185981 is about 230.1195408833.

The spelling of 12185981 in words is "twelve million, one hundred eighty-five thousand, nine hundred eighty-one".