20618000 has 120 divisors (see below), whose sum is σ = 54869256. Its totient is φ = 7488000.

The previous prime is 20617999. The next prime is 20618011. The reversal of 20618000 is 81602.

It can be written as a sum of positive squares in 12 ways, for example, as 20322064 + 295936 = 4508^2 + 544^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20618000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 337970 + ... + 338030.

Almost surely, 2^20618000 is an apocalyptic number.

20618000 is a gapful number since it is divisible by the number (20) 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 20618000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27434628).

20618000 is an abundant number, since it is smaller than the sum of its proper divisors (34251256).

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

20618000 is a wasteful number, since it uses less digits than its factorization.

20618000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 20618000 is about 4540.7047911090. The cubic root of 20618000 is about 274.2092989427.

Adding to 20618000 its reverse (81602), we get a palindrome (20699602).

The spelling of 20618000 in words is "twenty million, six hundred eighteen thousand".