211081728 has 240 divisors, whose sum is σ = 682643808. Its totient is φ = 57139200.

The previous prime is 211081723. The next prime is 211081751. The reversal of 211081728 is 827180112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 211081695 and 211081704.

It is not an unprimeable number, because it can be changed into a prime (211081723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6809073 + ... + 6809103.

Almost surely, 2^211081728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211081728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (341321904).

211081728 is an abundant number, since it is smaller than the sum of its proper divisors (471562080).

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

211081728 is a wasteful number, since it uses less digits than its factorization.

211081728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 30.

The square root of 211081728 is about 14528.6519677498. The cubic root of 211081728 is about 595.4110362765.

It can be divided in two parts, 2110 and 81728, that added together give a palindrome (83838).

The spelling of 211081728 in words is "two hundred eleven million, eighty-one thousand, seven hundred twenty-eight".