21002123233 has 32 divisors (see below), whose sum is σ = 27251168000. Its totient is φ = 15718219776.

The previous prime is 21002123231. The next prime is 21002123237. The reversal of 21002123233 is 33232120012.

It is not a de Polignac number, because 21002123233 - 2¹ = 21002123231 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a self number, because there is not a number n which added to its sum of digits gives 21002123233.

It is not an unprimeable number, because it can be changed into a prime (21002123231) 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, 1154593 + ... + 1172641.

It is an arithmetic number, because the mean of its divisors is an integer number (851599000).

Almost surely, 2^21002123233 is an apocalyptic number.

It is an amenable number.

21002123233 is a deficient number, since it is larger than the sum of its proper divisors (6249044767).

21002123233 is a wasteful number, since it uses less digits than its factorization.

21002123233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18761.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21002123233 its reverse (33232120012), we get a palindrome (54234243245).

The spelling of 21002123233 in words is "twenty-one billion, two million, one hundred twenty-three thousand, two hundred thirty-three".