221031200 has 144 divisors (see below), whose sum is σ = 593540136. Its totient is φ = 79872000.

The previous prime is 221031193. The next prime is 221031203. The reversal of 221031200 is 2130122.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 53173264 + 167857936 = 7292^2 + 12956^2 .

It is not an unprimeable number, because it can be changed into a prime (221031203) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 551000 + ... + 551400.

Almost surely, 2^221031200 is an apocalyptic number.

221031200 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 221031200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (296770068).

221031200 is an abundant number, since it is smaller than the sum of its proper divisors (372508936).

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

221031200 is a wasteful number, since it uses less digits than its factorization.

221031200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487 (or 474 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 221031200 is about 14867.1180798432. The cubic root of 221031200 is about 604.6228097617.

Adding to 221031200 its reverse (2130122), we get a palindrome (223161322).

The spelling of 221031200 in words is "two hundred twenty-one million, thirty-one thousand, two hundred".