21443253255216 has 320 divisors, whose sum is σ = 67293980131840. Its totient is φ = 6497519846400.

The previous prime is 21443253255169. The next prime is 21443253255239. The reversal of 21443253255216 is 61255235234412.

21443253255216 is a `hidden beast` number, since 2 + 1 + 4 + 4 + 32 + 53 + 2 + 552 + 16 = 666.

It is a super-2 number, since 2×21443253255216² (a number of 27 digits) contains 22 as substring.

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, 1750034946 + ... + 1750047198.

It is an arithmetic number, because the mean of its divisors is an integer number (210293687912).

Almost surely, 2^{21443253255216} is an apocalyptic number.

21443253255216 is a gapful number since it is divisible by the number (26) 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 21443253255216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33646990065920).

21443253255216 is an abundant number, since it is smaller than the sum of its proper divisors (45850726876624).

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

21443253255216 is a wasteful number, since it uses less digits than its factorization.

21443253255216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17001 (or 16989 counting only the distinct ones).

The product of its digits is 1728000, while the sum is 45.

Adding to 21443253255216 its reverse (61255235234412), we get a palindrome (82698488489628).

The spelling of 21443253255216 in words is "twenty-one trillion, four hundred forty-three billion, two hundred fifty-three million, two hundred fifty-five thousand, two hundred sixteen".