21034124020 has 96 divisors (see below), whose sum is σ = 54442741248. Its totient is φ = 6647450112.

The previous prime is 21034124017. The next prime is 21034124029. The reversal of 21034124020 is 2042143012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21034124029) by changing a digit.

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, 1326177 + ... + 1341943.

It is an arithmetic number, because the mean of its divisors is an integer number (567111888).

Almost surely, 2^21034124020 is an apocalyptic number.

21034124020 is a gapful number since it is divisible by the number (20) 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 21034124020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27221370624).

21034124020 is an abundant number, since it is smaller than the sum of its proper divisors (33408617228).

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

21034124020 is a wasteful number, since it uses less digits than its factorization.

21034124020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16529 (or 16527 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21034124020 its reverse (2042143012), we get a palindrome (23076267032).

The spelling of 21034124020 in words is "twenty-one billion, thirty-four million, one hundred twenty-four thousand, twenty".