221305000 has 80 divisors (see below), whose sum is σ = 592685280. Its totient is φ = 75864000.

The previous prime is 221304971. The next prime is 221305009. The reversal of 221305000 is 503122.

It is not an unprimeable number, because it can be changed into a prime (221305009) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 31839 + ... + 38161.

It is an arithmetic number, because the mean of its divisors is an integer number (7408566).

Almost surely, 2^221305000 is an apocalyptic number.

221305000 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 221305000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (296342640).

221305000 is an abundant number, since it is smaller than the sum of its proper divisors (371380280).

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

221305000 is an equidigital number, since it uses as much as digits as its factorization.

221305000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6356 (or 6337 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 221305000 is about 14876.3234705353. The cubic root of 221305000 is about 604.8723633939.

Adding to 221305000 its reverse (503122), we get a palindrome (221808122).

The spelling of 221305000 in words is "two hundred twenty-one million, three hundred five thousand".