21220111001268 has 216 divisors, whose sum is σ = 59006986182144. Its totient is φ = 6653840774400.

The previous prime is 21220111001267. The next prime is 21220111001281. The reversal of 21220111001268 is 86210011102212.

It is a super-2 number, since 2×21220111001268² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220111001267) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 941807163 + ... + 941829693.

It is an arithmetic number, because the mean of its divisors is an integer number (273180491584).

Almost surely, 2^{21220111001268} 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 21220111001268, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29503493091072).

21220111001268 is an abundant number, since it is smaller than the sum of its proper divisors (37786875180876).

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

21220111001268 is a wasteful number, since it uses less digits than its factorization.

21220111001268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24687 (or 24664 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The spelling of 21220111001268 in words is "twenty-one trillion, two hundred twenty billion, one hundred eleven million, one thousand, two hundred sixty-eight".