221234556 has 48 divisors (see below), whose sum is σ = 552325760. Its totient is φ = 68713920.

The previous prime is 221234543. The next prime is 221234599. The reversal of 221234556 is 655432122.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5955 + ... + 21861.

Almost surely, 2^221234556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221234556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276162880).

221234556 is an abundant number, since it is smaller than the sum of its proper divisors (331091204).

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

221234556 is a wasteful number, since it uses less digits than its factorization.

221234556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15994 (or 15992 counting only the distinct ones).

The product of its digits is 14400, while the sum is 30.

The square root of 221234556 is about 14873.9556272029. The cubic root of 221234556 is about 604.8081772396.

Adding to 221234556 its reverse (655432122), we get a palindrome (876666678).

The spelling of 221234556 in words is "two hundred twenty-one million, two hundred thirty-four thousand, five hundred fifty-six".