221881600 has 108 divisors (see below), whose sum is σ = 564636604. Its totient is φ = 86261760.

The previous prime is 221881589. The next prime is 221881609. The reversal of 221881600 is 6188122.

It can be written as a sum of positive squares in 6 ways, for example, as 8020224 + 213861376 = 2832^2 + 14624^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221881609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 236332 + ... + 237268.

Almost surely, 2^221881600 is an apocalyptic number.

221881600 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 221881600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282318302).

221881600 is an abundant number, since it is smaller than the sum of its proper divisors (342755004).

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

221881600 is an equidigital number, since it uses as much as digits as its factorization.

221881600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000 (or 981 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 221881600 is about 14895.6906519973. The cubic root of 221881600 is about 605.3972301939.

The spelling of 221881600 in words is "two hundred twenty-one million, eight hundred eighty-one thousand, six hundred".