221752128 has 56 divisors (see below), whose sum is σ = 631858528. Its totient is φ = 68230656.

The previous prime is 221752127. The next prime is 221752147. The reversal of 221752128 is 821257122.

221752128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221752095 and 221752104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221752123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41926 + ... + 46917.

It is an arithmetic number, because the mean of its divisors is an integer number (11283188).

Almost surely, 2^221752128 is an apocalyptic number.

It is an amenable number.

221752128 is an abundant number, since it is smaller than the sum of its proper divisors (410106400).

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

221752128 is a wasteful number, since it uses less digits than its factorization.

221752128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88871 (or 88861 counting only the distinct ones).

The product of its digits is 4480, while the sum is 30.

The square root of 221752128 is about 14891.3440629112. The cubic root of 221752128 is about 605.2794538049.

It can be divided in two parts, 2217 and 52128, that added together give a palindrome (54345).

The spelling of 221752128 in words is "two hundred twenty-one million, seven hundred fifty-two thousand, one hundred twenty-eight".