21043433334 has 128 divisors (see below), whose sum is σ = 53326061568. Its totient is φ = 5377570560.

The previous prime is 21043433329. The next prime is 21043433347. The reversal of 21043433334 is 43333434012.

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 63 ways as a sum of consecutive naturals, for example, 7755162 + ... + 7757874.

It is an arithmetic number, because the mean of its divisors is an integer number (416609856).

Almost surely, 2^21043433334 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21043433334, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26663030784).

21043433334 is an abundant number, since it is smaller than the sum of its proper divisors (32282628234).

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

21043433334 is a wasteful number, since it uses less digits than its factorization.

21043433334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3002.

The product of its (nonzero) digits is 31104, while the sum is 30.

Adding to 21043433334 its reverse (43333434012), we get a palindrome (64376867346).

The spelling of 21043433334 in words is "twenty-one billion, forty-three million, four hundred thirty-three thousand, three hundred thirty-four".