220621728 has 24 divisors (see below), whose sum is σ = 579132288. Its totient is φ = 73540544.

The previous prime is 220621717. The next prime is 220621757. The reversal of 220621728 is 827126022.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 220621695 and 220621704.

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 3 ways as a sum of consecutive naturals, for example, 1148976 + ... + 1149167.

It is an arithmetic number, because the mean of its divisors is an integer number (24130512).

Almost surely, 2^220621728 is an apocalyptic number.

It is an amenable number.

220621728 is an abundant number, since it is smaller than the sum of its proper divisors (358510560).

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

220621728 is a wasteful number, since it uses less digits than its factorization.

220621728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2298156 (or 2298148 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 220621728 is about 14853.3406343489. The cubic root of 220621728 is about 604.2492137094.

The spelling of 220621728 in words is "two hundred twenty million, six hundred twenty-one thousand, seven hundred twenty-eight".