221220084 has 12 divisors (see below), whose sum is σ = 516180224. Its totient is φ = 73740024.

The previous prime is 221220067. The next prime is 221220089. The reversal of 221220084 is 480022122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 221220084.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221220089) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9217492 + ... + 9217515.

Almost surely, 2^221220084 is an apocalyptic number.

It is an amenable number.

221220084 is an abundant number, since it is smaller than the sum of its proper divisors (294960140).

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

221220084 is a wasteful number, since it uses less digits than its factorization.

221220084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18435014 (or 18435012 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 221220084 is about 14873.4691313089. The cubic root of 221220084 is about 604.7949891630.

The spelling of 221220084 in words is "two hundred twenty-one million, two hundred twenty thousand, eighty-four".