211005 has 20 divisors (see below), whose sum is σ = 378972. Its totient is φ = 112320.

The previous prime is 210967. The next prime is 211007. The reversal of 211005 is 500112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 68121 + 142884 = 261^2 + 378^2 .

It is not a de Polignac number, because 211005 - 2¹² = 206909 is a prime.

It is a super-2 number, since 2×211005² = 89046220050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211007) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 145 + ... + 665.

2²¹¹⁰⁰⁵ is an apocalyptic number.

It is an amenable number.

211005 is a deficient number, since it is larger than the sum of its proper divisors (167967).

211005 is an equidigital number, since it uses as much as digits as its factorization.

211005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The square root of 211005 is about 459.3528055863. The cubic root of 211005 is about 59.5338883758.

Adding to 211005 its reverse (500112), we get a palindrome (711117).

The spelling of 211005 in words is "two hundred eleven thousand, five".