18081481 has 8 divisors (see below), whose sum is σ = 19778400. Its totient is φ = 16393440.

The previous prime is 18081461. The next prime is 18081527. The reversal of 18081481 is 18418081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18081481 is a prime.

It is a super-2 number, since 2×18081481² = 653879910306722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18081431) 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 7 ways as a sum of consecutive naturals, for example, 2490 + ... + 6508.

It is an arithmetic number, because the mean of its divisors is an integer number (2472300).

Almost surely, 2^18081481 is an apocalyptic number.

18081481 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18081481 is a deficient number, since it is larger than the sum of its proper divisors (1696919).

18081481 is a wasteful number, since it uses less digits than its factorization.

18081481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4439.

The product of its (nonzero) digits is 2048, while the sum is 31.

The square root of 18081481 is about 4252.2324724784. The cubic root of 18081481 is about 262.4689898364.

The spelling of 18081481 in words is "eighteen million, eighty-one thousand, four hundred eighty-one".