18182181 has 8 divisors (see below), whose sum is σ = 24465760. Its totient is φ = 12010032.

The previous prime is 18182149. The next prime is 18182201. The reversal of 18182181 is 18128181.

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

It is not a de Polignac number, because 18182181 - 2⁵ = 18182149 is a prime.

It is a super-2 number, since 2×18182181² = 661183411833522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18182141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27475 + ... + 28128.

It is an arithmetic number, because the mean of its divisors is an integer number (3058220).

Almost surely, 2^18182181 is an apocalyptic number.

It is an amenable number.

18182181 is a deficient number, since it is larger than the sum of its proper divisors (6283579).

18182181 is a wasteful number, since it uses less digits than its factorization.

18182181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55715.

The product of its digits is 1024, while the sum is 30.

The square root of 18182181 is about 4264.0568711029. The cubic root of 18182181 is about 262.9553385009.

The spelling of 18182181 in words is "eighteen million, one hundred eighty-two thousand, one hundred eighty-one".