221111100000 has 576 divisors, whose sum is σ = 921316032000. Its totient is φ = 50535360000.

The previous prime is 221111099971. The next prime is 221111100011. The reversal of 221111100000 is 1111122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 18894151 + ... + 18905849.

It is an arithmetic number, because the mean of its divisors is an integer number (1599507000).

Almost surely, 2^221111100000 is an apocalyptic number.

221111100000 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 221111100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460658016000).

221111100000 is an abundant number, since it is smaller than the sum of its proper divisors (700204932000).

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

221111100000 is an equidigital number, since it uses as much as digits as its factorization.

221111100000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11750 (or 11716 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 221111100000 its reverse (1111122), we get a palindrome (221112211122).

The spelling of 221111100000 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred thousand".