20180005 has 4 divisors (see below), whose sum is σ = 24216012. Its totient is φ = 16144000.

The previous prime is 20179987. The next prime is 20180009. The reversal of 20180005 is 50008102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50008102 = 2 ⋅25004051.

It can be written as a sum of positive squares in 2 ways, for example, as 14424804 + 5755201 = 3798^2 + 2399^2 .

It is not a de Polignac number, because 20180005 - 2⁷ = 20179877 is a prime.

It is a Duffinian number.

It is a plaindrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20180009) 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 3 ways as a sum of consecutive naturals, for example, 2017996 + ... + 2018005.

It is an arithmetic number, because the mean of its divisors is an integer number (6054003).

Almost surely, 2^20180005 is an apocalyptic number.

It is an amenable number.

20180005 is a deficient number, since it is larger than the sum of its proper divisors (4036007).

20180005 is an equidigital number, since it uses as much as digits as its factorization.

20180005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4036006.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 20180005 is about 4492.2160455615. The cubic root of 20180005 is about 272.2536785961.

Adding to 20180005 its reverse (50008102), we get a palindrome (70188107).

The spelling of 20180005 in words is "twenty million, one hundred eighty thousand, five".