223121220 has 192 divisors, whose sum is σ = 743178240. Its totient is φ = 48964608.

The previous prime is 223121207. The next prime is 223121233. The reversal of 223121220 is 22121322.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (223121207) and next prime (223121233).

It is a super-3 number, since 3×223121220³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 223121220.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 1756797 + ... + 1756923.

It is an arithmetic number, because the mean of its divisors is an integer number (3870720).

Almost surely, 2^223121220 is an apocalyptic number.

223121220 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 223121220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (371589120).

223121220 is an abundant number, since it is smaller than the sum of its proper divisors (520057020).

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

223121220 is a wasteful number, since it uses less digits than its factorization.

223121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 223121220 is about 14937.2427174496. The cubic root of 223121220 is about 606.5225589901.

Adding to 223121220 its reverse (22121322), we get a palindrome (245242542).

It can be divided in two parts, 22312 and 1220, that added together give a palindrome (23532).

The spelling of 223121220 in words is "two hundred twenty-three million, one hundred twenty-one thousand, two hundred twenty".