18007705 has 4 divisors (see below), whose sum is σ = 21609252. Its totient is φ = 14406160.

The previous prime is 18007697. The next prime is 18007723. The reversal of 18007705 is 50770081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7529536 + 10478169 = 2744^2 + 3237^2 .

It is not a de Polignac number, because 18007705 - 2³ = 18007697 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 1800766 + ... + 1800775.

It is an arithmetic number, because the mean of its divisors is an integer number (5402313).

Almost surely, 2^18007705 is an apocalyptic number.

It is an amenable number.

18007705 is a deficient number, since it is larger than the sum of its proper divisors (3601547).

18007705 is an equidigital number, since it uses as much as digits as its factorization.

18007705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3601546.

The product of its (nonzero) digits is 1960, while the sum is 28.

The square root of 18007705 is about 4243.5486329250. The cubic root of 18007705 is about 262.1115281837. Note that the first 3 decimals are identical.

Adding to 18007705 its reverse (50770081), we get a palindrome (68777786).

The spelling of 18007705 in words is "eighteen million, seven thousand, seven hundred five".