221022220 has 12 divisors (see below), whose sum is σ = 464146704. Its totient is φ = 88408880.

The previous prime is 221022211. The next prime is 221022229. The reversal of 221022220 is 22220122.

It is an interprime number because it is at equal distance from previous prime (221022211) and next prime (221022229).

It is a self number, because there is not a number n which added to its sum of digits gives 221022220.

It is not an unprimeable number, because it can be changed into a prime (221022229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5525536 + ... + 5525575.

It is an arithmetic number, because the mean of its divisors is an integer number (38678892).

Almost surely, 2^221022220 is an apocalyptic number.

221022220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221022220 is an abundant number, since it is smaller than the sum of its proper divisors (243124484).

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

221022220 is a wasteful number, since it uses less digits than its factorization.

221022220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11051120 (or 11051118 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 221022220 is about 14866.8160680086. The cubic root of 221022220 is about 604.6146214964.

Adding to 221022220 its reverse (22220122), we get a palindrome (243242342).

The spelling of 221022220 in words is "two hundred twenty-one million, twenty-two thousand, two hundred twenty".