21818210233 has 32 divisors (see below), whose sum is σ = 23355164160. Its totient is φ = 20347514880.

The previous prime is 21818210231. The next prime is 21818210263. The reversal of 21818210233 is 33201281812.

It is a cyclic number.

It is not a de Polignac number, because 21818210233 - 2¹ = 21818210231 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21818210195 and 21818210204.

It is not an unprimeable number, because it can be changed into a prime (21818210231) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61807785 + ... + 61808137.

It is an arithmetic number, because the mean of its divisors is an integer number (729848880).

Almost surely, 2^21818210233 is an apocalyptic number.

It is an amenable number.

21818210233 is a deficient number, since it is larger than the sum of its proper divisors (1536953927).

21818210233 is a wasteful number, since it uses less digits than its factorization.

21818210233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 897.

The product of its (nonzero) digits is 4608, while the sum is 31.

The spelling of 21818210233 in words is "twenty-one billion, eight hundred eighteen million, two hundred ten thousand, two hundred thirty-three".