21589409418220 has 384 divisors, whose sum is σ = 54007784570880. Its totient is φ = 7096639979520.

The previous prime is 21589409418197. The next prime is 21589409418223. The reversal of 21589409418220 is 2281490498512.

It is a super-2 number, since 2×21589409418220² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21589409418223) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 58826728477 + ... + 58826728843.

It is an arithmetic number, because the mean of its divisors is an integer number (140645272320).

Almost surely, 2^{21589409418220} is an apocalyptic number.

21589409418220 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 21589409418220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27003892285440).

21589409418220 is an abundant number, since it is smaller than the sum of its proper divisors (32418375152660).

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

21589409418220 is a wasteful number, since it uses less digits than its factorization.

21589409418220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1113 (or 1111 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 55.

The spelling of 21589409418220 in words is "twenty-one trillion, five hundred eighty-nine billion, four hundred nine million, four hundred eighteen thousand, two hundred twenty".