199071081 has 32 divisors (see below), whose sum is σ = 322521600. Its totient is φ = 120353040.

The previous prime is 199071077. The next prime is 199071143. The reversal of 199071081 is 180170991.

199071081 is a nontrivial binomial coefficient, being equal to C(19954, 2).

It is not a de Polignac number, because 199071081 - 2² = 199071077 is a prime.

It is a super-2 number, since 2×199071081² = 79258590581017122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (199071011) 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 in 31 ways as a sum of consecutive naturals, for example, 219030 + ... + 219936.

It is an arithmetic number, because the mean of its divisors is an integer number (10078800).

Almost surely, 2^199071081 is an apocalyptic number.

199071081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

199071081 is the 19953-rd triangular number and also the 9977-th hexagonal number.

It is an amenable number.

199071081 is a deficient number, since it is larger than the sum of its proper divisors (123450519).

199071081 is a wasteful number, since it uses less digits than its factorization.

199071081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1666 (or 1660 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 36.

The square root of 199071081 is about 14109.2551539761. The cubic root of 199071081 is about 583.8967504104.

The spelling of 199071081 in words is "one hundred ninety-nine million, seventy-one thousand, eighty-one".