17820018 has 12 divisors (see below), whose sum is σ = 38610078. Its totient is φ = 5940000.

The previous prime is 17820013. The next prime is 17820053. The reversal of 17820018 is 81002871.

It can be written as a sum of positive squares in only one way, i.e., 17614809 + 205209 = 4197^2 + 453^2 .

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 17819973 and 17820000.

It is not an unprimeable number, because it can be changed into a prime (17820013) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 494983 + ... + 495018.

Almost surely, 2^17820018 is an apocalyptic number.

17820018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

17820018 is an abundant number, since it is smaller than the sum of its proper divisors (20790060).

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

17820018 is a wasteful number, since it uses less digits than its factorization.

17820018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 990009 (or 990006 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 27.

The square root of 17820018 is about 4221.3763158477. The cubic root of 17820018 is about 261.1977186805.

Adding to 17820018 its reverse (81002871), we get a palindrome (98822889).

The spelling of 17820018 in words is "seventeen million, eight hundred twenty thousand, eighteen".