21111124352 has 128 divisors (see below), whose sum is σ = 45627170400. Its totient is φ = 9696706560.

The previous prime is 21111124327. The next prime is 21111124357. The reversal of 21111124352 is 25342111112.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111124357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19243868 + ... + 19244964.

Almost surely, 2^21111124352 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 21111124352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22813585200).

21111124352 is an abundant number, since it is smaller than the sum of its proper divisors (24516046048).

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

21111124352 is a wasteful number, since it uses less digits than its factorization.

21111124352 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364 (or 1352 counting only the distinct ones).

The product of its digits is 480, while the sum is 23.

Adding to 21111124352 its reverse (25342111112), we get a palindrome (46453235464).

The spelling of 21111124352 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-four thousand, three hundred fifty-two".