221030556 has 24 divisors (see below), whose sum is σ = 517184640. Its totient is φ = 73470192.

The previous prime is 221030543. The next prime is 221030561. The reversal of 221030556 is 655030122.

It is a congruent number.

It is an unprimeable number.

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, 21346 + ... + 29961.

It is an arithmetic number, because the mean of its divisors is an integer number (21549360).

Almost surely, 2^221030556 is an apocalyptic number.

It is an amenable number.

221030556 is an abundant number, since it is smaller than the sum of its proper divisors (296154084).

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

221030556 is a wasteful number, since it uses less digits than its factorization.

221030556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51673 (or 51671 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 221030556 is about 14867.0964212922. The cubic root of 221030556 is about 604.6222225483.

Adding to 221030556 its reverse (655030122), we get a palindrome (876060678).

The spelling of 221030556 in words is "two hundred twenty-one million, thirty thousand, five hundred fifty-six".