221531450 has 72 divisors (see below), whose sum is σ = 504655200. Its totient is φ = 71940960.

The previous prime is 221531449. The next prime is 221531483. The reversal of 221531450 is 54135122.

221531450 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 44171 + ... + 48929.

It is an arithmetic number, because the mean of its divisors is an integer number (7009100).

Almost surely, 2^221531450 is an apocalyptic number.

221531450 is an abundant number, since it is smaller than the sum of its proper divisors (283123750).

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

221531450 is a wasteful number, since it uses less digits than its factorization.

221531450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4804 (or 4792 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 221531450 is about 14883.9326120485. The cubic root of 221531450 is about 605.0786046356.

Adding to 221531450 its reverse (54135122), we get a palindrome (275666572).

The spelling of 221531450 in words is "two hundred twenty-one million, five hundred thirty-one thousand, four hundred fifty".