221210440 has 128 divisors (see below), whose sum is σ = 563915520. Its totient is φ = 77414400.

The previous prime is 221210419. The next prime is 221210449. The reversal of 221210440 is 44012122.

It is not an unprimeable number, because it can be changed into a prime (221210449) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2280472 + ... + 2280568.

It is an arithmetic number, because the mean of its divisors is an integer number (4405590).

Almost surely, 2^221210440 is an apocalyptic number.

221210440 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 221210440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281957760).

221210440 is an abundant number, since it is smaller than the sum of its proper divisors (342705080).

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

221210440 is a wasteful number, since it uses less digits than its factorization.

221210440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 221210440 is about 14873.1449263429. The cubic root of 221210440 is about 604.7862004377.

Adding to 221210440 its reverse (44012122), we get a palindrome (265222562).

The spelling of 221210440 in words is "two hundred twenty-one million, two hundred ten thousand, four hundred forty".