18121205 has 8 divisors (see below), whose sum is σ = 22447104. Its totient is φ = 14029200.

The previous prime is 18121163. The next prime is 18121211. The reversal of 18121205 is 50212181.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-18121205 is a prime.

It is a Duffinian number.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 58301 + ... + 58610.

It is an arithmetic number, because the mean of its divisors is an integer number (2805888).

Almost surely, 2^18121205 is an apocalyptic number.

It is an amenable number.

18121205 is a deficient number, since it is larger than the sum of its proper divisors (4325899).

18121205 is a wasteful number, since it uses less digits than its factorization.

18121205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116947.

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 18121205 is about 4256.9008680024. The cubic root of 18121205 is about 262.6610591349.

Adding to 18121205 its reverse (50212181), we get a palindrome (68333386).

The spelling of 18121205 in words is "eighteen million, one hundred twenty-one thousand, two hundred five".