1800018 has 24 divisors (see below), whose sum is σ = 4255056. Its totient is φ = 545400.

The previous prime is 1800017. The next prime is 1800037. The reversal of 1800018 is 8100081.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1800017) 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 11 ways as a sum of consecutive naturals, for example, 4348 + ... + 4743.

It is an arithmetic number, because the mean of its divisors is an integer number (177294).

2^1800018 is an apocalyptic number.

1800018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1800018 is an abundant number, since it is smaller than the sum of its proper divisors (2455038).

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

1800018 is a wasteful number, since it uses less digits than its factorization.

1800018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9110 (or 9107 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

The square root of 1800018 is about 1341.6474946870. The cubic root of 1800018 is about 121.6444453902.

1800018 divided by its sum of digits (18) gives a palindrome (100001).

Adding to 1800018 its reverse (8100081), we get a palindrome (9900099).

The spelling of 1800018 in words is "one million, eight hundred thousand, eighteen".