221438180 has 24 divisors (see below), whose sum is σ = 465514560. Its totient is φ = 88481120.

The previous prime is 221438143. The next prime is 221438183. The reversal of 221438180 is 81834122.

It is not an unprimeable number, because it can be changed into a prime (221438183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15251 + ... + 25989.

It is an arithmetic number, because the mean of its divisors is an integer number (19396440).

Almost surely, 2^221438180 is an apocalyptic number.

221438180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221438180 is an abundant number, since it is smaller than the sum of its proper divisors (244076380).

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

221438180 is a wasteful number, since it uses less digits than its factorization.

221438180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11779 (or 11777 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 221438180 is about 14880.7990376861. The cubic root of 221438180 is about 604.9936752293.

The spelling of 221438180 in words is "two hundred twenty-one million, four hundred thirty-eight thousand, one hundred eighty".