18146981 has 2 divisors, whose sum is σ = 18146982. Its totient is φ = 18146980.

The previous prime is 18146971. The next prime is 18146993. The reversal of 18146981 is 18964181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10666756 + 7480225 = 3266^2 + 2735^2 .

It is a cyclic number.

It is not a de Polignac number, because 18146981 - 2⁶ = 18146917 is a prime.

It is a super-2 number, since 2×18146981² = 658625838828722, 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 (18146911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9073490 + 9073491.

It is an arithmetic number, because the mean of its divisors is an integer number (9073491).

Almost surely, 2^18146981 is an apocalyptic number.

It is an amenable number.

18146981 is a deficient number, since it is larger than the sum of its proper divisors (1).

18146981 is an equidigital number, since it uses as much as digits as its factorization.

18146981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 38.

The square root of 18146981 is about 4259.9273467983. The cubic root of 18146981 is about 262.7855384193.

The spelling of 18146981 in words is "eighteen million, one hundred forty-six thousand, nine hundred eighty-one".