183199981 has 2 divisors, whose sum is σ = 183199982. Its totient is φ = 183199980.

The previous prime is 183199969. The next prime is 183199999. The reversal of 183199981 is 189991381.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110439081 + 72760900 = 10509^2 + 8530^2 .

It is a cyclic number.

It is not a de Polignac number, because 183199981 - 2⁵ = 183199949 is a prime.

It is a super-2 number, since 2×183199981² = 67124466076800722, 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 (183199901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 91599990 + 91599991.

It is an arithmetic number, because the mean of its divisors is an integer number (91599991).

Almost surely, 2^183199981 is an apocalyptic number.

It is an amenable number.

183199981 is a deficient number, since it is larger than the sum of its proper divisors (1).

183199981 is an equidigital number, since it uses as much as digits as its factorization.

183199981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 49.

The square root of 183199981 is about 13535.1387506741. The cubic root of 183199981 is about 567.9478695214.

The spelling of 183199981 in words is "one hundred eighty-three million, one hundred ninety-nine thousand, nine hundred eighty-one".