21054430012 has 96 divisors (see below), whose sum is σ = 48533022720. Its totient is φ = 7751493120.

The previous prime is 21054430009. The next prime is 21054430037. The reversal of 21054430012 is 21003445012.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 394728 + ... + 444880.

It is an arithmetic number, because the mean of its divisors is an integer number (505552320).

Almost surely, 2^21054430012 is an apocalyptic number.

21054430012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21054430012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24266511360).

21054430012 is an abundant number, since it is smaller than the sum of its proper divisors (27478592708).

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

21054430012 is a wasteful number, since it uses less digits than its factorization.

21054430012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50251 (or 50249 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 21054430012 its reverse (21003445012), we get a palindrome (42057875024).

The spelling of 21054430012 in words is "twenty-one billion, fifty-four million, four hundred thirty thousand, twelve".