211616 has 24 divisors (see below), whose sum is σ = 442260. Its totient is φ = 99328.

The previous prime is 211597. The next prime is 211619. The reversal of 211616 is 616112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 211600 + 16 = 460^2 + 4^2 .

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a nialpdrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 211594 and 211603.

It is not an unprimeable number, because it can be changed into a prime (211619) by changing a digit.

211616 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 350 + ... + 738.

2²¹¹⁶¹⁶ 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 211616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221130).

211616 is an abundant number, since it is smaller than the sum of its proper divisors (230644).

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

211616 is a wasteful number, since it uses less digits than its factorization.

211616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416 (or 408 counting only the distinct ones).

The product of its digits is 72, while the sum is 17.

The square root of 211616 is about 460.0173909756. The cubic root of 211616 is about 59.5912964183.

Adding to 211616 its reverse (616112), we get a palindrome (827728).

Subtracting 211616 from its reverse (616112), we obtain a square (404496 = 636²).

It can be divided in two parts, 2116 and 16, that multiplied together give a square (33856 = 184²).

The spelling of 211616 in words is "two hundred eleven thousand, six hundred sixteen".