220221555 has 16 divisors (see below), whose sum is σ = 359852544. Its totient is φ = 114952160.

The previous prime is 220221541. The next prime is 220221583. The reversal of 220221555 is 555122022.

It is not a de Polignac number, because 220221555 - 2⁴ = 220221539 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 155481 + ... + 156890.

It is an arithmetic number, because the mean of its divisors is an integer number (22490784).

Almost surely, 2^220221555 is an apocalyptic number.

220221555 is a deficient number, since it is larger than the sum of its proper divisors (139630989).

220221555 is a wasteful number, since it uses less digits than its factorization.

220221555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312426.

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 220221555 is about 14839.8637123122. The cubic root of 220221555 is about 603.8836550243.

Adding to 220221555 its reverse (555122022), we get a palindrome (775343577).

The spelling of 220221555 in words is "two hundred twenty million, two hundred twenty-one thousand, five hundred fifty-five".