21518668834233 has 8 divisors (see below), whose sum is σ = 28703856594048. Its totient is φ = 14339630148624.

The previous prime is 21518668834217. The next prime is 21518668834237. The reversal of 21518668834233 is 33243886681512.

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

It is not a de Polignac number, because 21518668834233 - 2⁴ = 21518668834217 is a prime.

It is a Smith number, since the sum of its digits (60) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21518668834237) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1537260385 + ... + 1537274382.

It is an arithmetic number, because the mean of its divisors is an integer number (3587982074256).

Almost surely, 2^{21518668834233} is an apocalyptic number.

It is an amenable number.

21518668834233 is a deficient number, since it is larger than the sum of its proper divisors (7185187759815).

21518668834233 is a wasteful number, since it uses less digits than its factorization.

21518668834233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3074537103.

The product of its digits is 39813120, while the sum is 60.

The spelling of 21518668834233 in words is "twenty-one trillion, five hundred eighteen billion, six hundred sixty-eight million, eight hundred thirty-four thousand, two hundred thirty-three".