221018238 has 24 divisors (see below), whose sum is σ = 547283568. Its totient is φ = 63148032.

The previous prime is 221018219. The next prime is 221018261. The reversal of 221018238 is 832810122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 876931 + ... + 877182.

It is an arithmetic number, because the mean of its divisors is an integer number (22803482).

Almost surely, 2^221018238 is an apocalyptic number.

221018238 is an abundant number, since it is smaller than the sum of its proper divisors (326265330).

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

221018238 is a wasteful number, since it uses less digits than its factorization.

221018238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1754128 (or 1754125 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 221018238 is about 14866.6821449845. The cubic root of 221018238 is about 604.6109905041.

The spelling of 221018238 in words is "two hundred twenty-one million, eighteen thousand, two hundred thirty-eight".