199367981 has 2 divisors, whose sum is σ = 199367982. Its totient is φ = 199367980.

The previous prime is 199367963. The next prime is 199367999. The reversal of 199367981 is 189763991.

It is a balanced prime because it is at equal distance from previous prime (199367963) and next prime (199367999).

It can be written as a sum of positive squares in only one way, i.e., 157000900 + 42367081 = 12530^2 + 6509^2 .

It is a cyclic number.

It is not a de Polignac number, because 199367981 - 2²⁶ = 132259117 is a prime.

It is a super-2 number, since 2×199367981² = 79495183696032722, 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 (199367941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99683990 + 99683991.

It is an arithmetic number, because the mean of its divisors is an integer number (99683991).

Almost surely, 2^199367981 is an apocalyptic number.

It is an amenable number.

199367981 is a deficient number, since it is larger than the sum of its proper divisors (1).

199367981 is an equidigital number, since it uses as much as digits as its factorization.

199367981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 734832, while the sum is 53.

The square root of 199367981 is about 14119.7726964707. The cubic root of 199367981 is about 584.1868860270.

The spelling of 199367981 in words is "one hundred ninety-nine million, three hundred sixty-seven thousand, nine hundred eighty-one".