21411050520 has 256 divisors, whose sum is σ = 71259264000. Its totient is φ = 5136857088.

The previous prime is 21411050509. The next prime is 21411050579. The reversal of 21411050520 is 2505011412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13559091 + ... + 13560669.

It is an arithmetic number, because the mean of its divisors is an integer number (278356500).

Almost surely, 2^21411050520 is an apocalyptic number.

21411050520 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 21411050520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35629632000).

21411050520 is an abundant number, since it is smaller than the sum of its proper divisors (49848213480).

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

21411050520 is a wasteful number, since it uses less digits than its factorization.

21411050520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1667 (or 1629 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 21411050520 its reverse (2505011412), we get a palindrome (23916061932).

The spelling of 21411050520 in words is "twenty-one billion, four hundred eleven million, fifty thousand, five hundred twenty".