220591728 has 240 divisors, whose sum is σ = 781155360. Its totient is φ = 59222016.

The previous prime is 220591703. The next prime is 220591747. The reversal of 220591728 is 827195022.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 220591692 and 220591701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 359550 + ... + 360162.

It is an arithmetic number, because the mean of its divisors is an integer number (3254814).

Almost surely, 2^220591728 is an apocalyptic number.

220591728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 220591728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (390577680).

220591728 is an abundant number, since it is smaller than the sum of its proper divisors (560563632).

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

220591728 is a wasteful number, since it uses less digits than its factorization.

220591728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 642 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 220591728 is about 14852.3307261857. The cubic root of 220591728 is about 604.2218239953.

The spelling of 220591728 in words is "two hundred twenty million, five hundred ninety-one thousand, seven hundred twenty-eight".