18082081 has 4 divisors (see below), whose sum is σ = 18182164. Its totient is φ = 17982000.

The previous prime is 18082019. The next prime is 18082087. The reversal of 18082081 is 18028081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18028081 = 31 ⋅581551.

It can be written as a sum of positive squares in 2 ways, for example, as 8503056 + 9579025 = 2916^2 + 3095^2 .

It is a cyclic number.

It is not a de Polignac number, because 18082081 - 2¹¹ = 18080033 is a prime.

It is a super-2 number, since 2×18082081² = 653923306581122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18082087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49770 + ... + 50131.

It is an arithmetic number, because the mean of its divisors is an integer number (4545541).

Almost surely, 2^18082081 is an apocalyptic number.

It is an amenable number.

18082081 is a deficient number, since it is larger than the sum of its proper divisors (100083).

18082081 is an equidigital number, since it uses as much as digits as its factorization.

18082081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100082.

The product of its (nonzero) digits is 1024, while the sum is 28.

The square root of 18082081 is about 4252.3030230688. The cubic root of 18082081 is about 262.4718929845.

It can be divided in two parts, 180820 and 81, that added together give a triangular number (180901 = T₆₀₁).

The spelling of 18082081 in words is "eighteen million, eighty-two thousand, eighty-one".