21018838233 has 16 divisors (see below), whose sum is σ = 30475647360. Its totient is φ = 12831849216.

The previous prime is 21018838229. The next prime is 21018838237. The reversal of 21018838233 is 33283881012.

It is an interprime number because it is at equal distance from previous prime (21018838229) and next prime (21018838237).

It is not a de Polignac number, because 21018838233 - 2² = 21018838229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21018838191 and 21018838200.

It is not an unprimeable number, because it can be changed into a prime (21018838237) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5567493 + ... + 5571266.

It is an arithmetic number, because the mean of its divisors is an integer number (1904727960).

Almost surely, 2^21018838233 is an apocalyptic number.

It is an amenable number.

21018838233 is a deficient number, since it is larger than the sum of its proper divisors (9456809127).

21018838233 is a wasteful number, since it uses less digits than its factorization.

21018838233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11138816.

The product of its (nonzero) digits is 55296, while the sum is 39.

The spelling of 21018838233 in words is "twenty-one billion, eighteen million, eight hundred thirty-eight thousand, two hundred thirty-three".