18280081 has 4 divisors (see below), whose sum is σ = 18289152. Its totient is φ = 18271012.

The previous prime is 18280069. The next prime is 18280099. The reversal of 18280081 is 18008281.

18280081 is a nontrivial binomial coefficient, being equal to C(6047, 2).

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18008281 = 569 ⋅31649.

It is not a de Polignac number, because 18280081 - 2⁷ = 18279953 is a prime.

It is a super-2 number, since 2×18280081² = 668322722733122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18280051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1 + ... + 6046.

It is an arithmetic number, because the mean of its divisors is an integer number (4572288).

Almost surely, 2^18280081 is an apocalyptic number.

18280081 is the 6046-th triangular number.

18280081 is the 2016-th centered nonagonal number.

It is an amenable number.

18280081 is a deficient number, since it is larger than the sum of its proper divisors (9071).

18280081 is an equidigital number, since it uses as much as digits as its factorization.

18280081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9070.

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

The square root of 18280081 is about 4275.5211378264. The cubic root of 18280081 is about 263.4264455571.

The spelling of 18280081 in words is "eighteen million, two hundred eighty thousand, eighty-one".