18181380 has 96 divisors (see below), whose sum is σ = 59076864. Its totient is φ = 4091904.

The previous prime is 18181367. The next prime is 18181391. The reversal of 18181380 is 8318181.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30364 + ... + 30956.

It is an arithmetic number, because the mean of its divisors is an integer number (615384).

Almost surely, 2^18181380 is an apocalyptic number.

18181380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18181380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29538432).

18181380 is an abundant number, since it is smaller than the sum of its proper divisors (40895484).

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

18181380 is a wasteful number, since it uses less digits than its factorization.

18181380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685 (or 683 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 30.

The square root of 18181380 is about 4263.9629454300. The cubic root of 18181380 is about 262.9514770221.

The spelling of 18181380 in words is "eighteen million, one hundred eighty-one thousand, three hundred eighty".