• 212² = 44944 is the smallest square that contains exactly four digits '4'.

• 212 can be written using four 4's:

See also 113.

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212 has 6 divisors (see below), whose sum is σ = 378. Its totient is φ = 104.

The previous prime is 211. The next prime is 223.

212 is nontrivially palindromic in base 3 and base 10.

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

212 is an esthetic number in base 3 and base 10, because in such bases its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 196 + 16 = 14^2 + 4^2 .

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is an alternating number because its digits alternate between even and odd.

212 is an undulating number in base 3 and base 10.

It is a plaindrome in base 9, base 12, base 13 and base 14.

It is a nialpdrome in base 4, base 6, base 7, base 15 and base 16.

It is a junction number, because it is equal to n+sod(n) for n = 196 and 205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23 + ... + 30.

It is an arithmetic number, because the mean of its divisors is an integer number (63).

It is an amenable number.

212 is a deficient number, since it is larger than the sum of its proper divisors (166).

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

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

The sum of its prime factors is 57 (or 55 counting only the distinct ones).

The product of its digits is 4, while the sum is 5.

The square root of 212 is about 14.5602197786. The cubic root of 212 is about 5.9627319577.

The spelling of 212 in words is "two hundred twelve", and thus it is an aban number and an iban number.