199105681 has 4 divisors (see below), whose sum is σ = 199144000. Its totient is φ = 199067364.

The previous prime is 199105679. The next prime is 199105703. The reversal of 199105681 is 186501991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 199105681 - 2¹ = 199105679 is a prime.

It is a super-2 number, since 2×199105681² = 79286144412947522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199105601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9861 + ... + 22258.

It is an arithmetic number, because the mean of its divisors is an integer number (49786000).

Almost surely, 2^199105681 is an apocalyptic number.

It is an amenable number.

199105681 is a deficient number, since it is larger than the sum of its proper divisors (38319).

199105681 is an equidigital number, since it uses as much as digits as its factorization.

199105681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38318.

The product of its (nonzero) digits is 19440, while the sum is 40.

The square root of 199105681 is about 14110.4812462226. The cubic root of 199105681 is about 583.9305769497.

The spelling of 199105681 in words is "one hundred ninety-nine million, one hundred five thousand, six hundred eighty-one".