220021100 has 108 divisors (see below), whose sum is σ = 529903584. Its totient is φ = 79223040.

The previous prime is 220021079. The next prime is 220021103. The reversal of 220021100 is 1120022.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220021103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 794162 + ... + 794438.

Almost surely, 2^220021100 is an apocalyptic number.

220021100 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 220021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264951792).

220021100 is an abundant number, since it is smaller than the sum of its proper divisors (309882484).

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

220021100 is a wasteful number, since it uses less digits than its factorization.

220021100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 344 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 220021100 is about 14833.1082379925. The cubic root of 220021100 is about 603.7003725638.

Adding to 220021100 its reverse (1120022), we get a palindrome (221141122).

The spelling of 220021100 in words is "two hundred twenty million, twenty-one thousand, one hundred".