21818173855018 has 8 divisors (see below), whose sum is σ = 34150185164448. Its totient is φ = 10434778800204.

The previous prime is 21818173855001. The next prime is 21818173855043. The reversal of 21818173855018 is 81055837181812.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 237154063596 + ... + 237154063687.

It is an arithmetic number, because the mean of its divisors is an integer number (4268773145556).

Almost surely, 2^{21818173855018} is an apocalyptic number.

21818173855018 is a deficient number, since it is larger than the sum of its proper divisors (12332011309430).

21818173855018 is a wasteful number, since it uses less digits than its factorization.

21818173855018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474308127308.

The product of its (nonzero) digits is 4300800, while the sum is 58.

The spelling of 21818173855018 in words is "twenty-one trillion, eight hundred eighteen billion, one hundred seventy-three million, eight hundred fifty-five thousand, eighteen".