21103233012 has 72 divisors (see below), whose sum is σ = 55119966720. Its totient is φ = 6800708160.

The previous prime is 21103232957. The next prime is 21103233059. The reversal of 21103233012 is 21033230112.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1177414 + ... + 1195202.

Almost surely, 2^21103233012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21103233012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27559983360).

21103233012 is an abundant number, since it is smaller than the sum of its proper divisors (34016733708).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21103233012 is a wasteful number, since it uses less digits than its factorization.

21103233012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18893 (or 18888 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21103233012 its reverse (21033230112), we get a palindrome (42136463124).

The spelling of 21103233012 in words is "twenty-one billion, one hundred three million, two hundred thirty-three thousand, twelve".