21558267064416 has 192 divisors, whose sum is σ = 57880145030400. Its totient is φ = 7023832621056.

The previous prime is 21558267064403. The next prime is 21558267064463. The reversal of 21558267064416 is 61446076285512.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 711173676 + ... + 711203988.

It is an arithmetic number, because the mean of its divisors is an integer number (301459088700).

Almost surely, 2^{21558267064416} 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 21558267064416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28940072515200).

21558267064416 is an abundant number, since it is smaller than the sum of its proper divisors (36321877965984).

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

21558267064416 is a wasteful number, since it uses less digits than its factorization.

21558267064416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31101 (or 31093 counting only the distinct ones).

The product of its (nonzero) digits is 19353600, while the sum is 57.

The spelling of 21558267064416 in words is "twenty-one trillion, five hundred fifty-eight billion, two hundred sixty-seven million, sixty-four thousand, four hundred sixteen".