18181340 has 24 divisors (see below), whose sum is σ = 38292912. Its totient is φ = 7251200.

The previous prime is 18181301. The next prime is 18181343. The reversal of 18181340 is 4318181.

It is a super-2 number, since 2×18181340² = 661122248391200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18181343) 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, 6887 + ... + 9153.

It is an arithmetic number, because the mean of its divisors is an integer number (1595538).

Almost surely, 2^18181340 is an apocalyptic number.

18181340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18181340 is an abundant number, since it is smaller than the sum of its proper divisors (20111572).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18181340 is a wasteful number, since it uses less digits than its factorization.

18181340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2677 (or 2675 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 18181340 is about 4263.9582549551. The cubic root of 18181340 is about 262.9512841863.

The spelling of 18181340 in words is "eighteen million, one hundred eighty-one thousand, three hundred forty".