221100000 has 288 divisors, whose sum is σ = 803198592. Its totient is φ = 52800000.

The previous prime is 221099999. The next prime is 221100037. The reversal of 221100000 is 1122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

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 47 ways as a sum of consecutive naturals, for example, 3299967 + ... + 3300033.

It is an arithmetic number, because the mean of its divisors is an integer number (2788884).

Almost surely, 2^221100000 is an apocalyptic number.

221100000 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 221100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401599296).

221100000 is an abundant number, since it is smaller than the sum of its proper divisors (582098592).

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

221100000 is an equidigital number, since it uses as much as digits as its factorization.

221100000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 221100000 is about 14869.4317309035. The cubic root of 221100000 is about 604.6855365533.

Adding to 221100000 its reverse (1122), we get a palindrome (221101122).

The spelling of 221100000 in words is "two hundred twenty-one million, one hundred thousand".