212521216 has 72 divisors (see below), whose sum is σ = 459164160. Its totient is φ = 97787904.

The previous prime is 212521201. The next prime is 212521249. The reversal of 212521216 is 612125212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204025 + ... + 205063.

It is an arithmetic number, because the mean of its divisors is an integer number (6377280).

Almost surely, 2^212521216 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 212521216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229582080).

212521216 is an abundant number, since it is smaller than the sum of its proper divisors (246642944).

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

212521216 is a wasteful number, since it uses less digits than its factorization.

212521216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1119 (or 1105 counting only the distinct ones).

The product of its digits is 480, while the sum is 22.

The square root of 212521216 is about 14578.1074217472. The cubic root of 212521216 is about 596.7614548631.

Adding to 212521216 its reverse (612125212), we get a palindrome (824646428).

The spelling of 212521216 in words is "two hundred twelve million, five hundred twenty-one thousand, two hundred sixteen".