217105252 has 96 divisors (see below), whose sum is σ = 490533120. Its totient is φ = 81768960.

The previous prime is 217105201. The next prime is 217105261. The reversal of 217105252 is 252501712.

It is a super-4 number, since 4×217105252⁴ (a number of 34 digits) contains 4444 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1382758 + ... + 1382914.

It is an arithmetic number, because the mean of its divisors is an integer number (5109720).

Almost surely, 2^217105252 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 217105252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (245266560).

217105252 is an abundant number, since it is smaller than the sum of its proper divisors (273427868).

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

217105252 is a wasteful number, since it uses less digits than its factorization.

217105252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 217105252 is about 14734.4919152307. The cubic root of 217105252 is about 601.0216409105.

Adding to 217105252 its reverse (252501712), we get a palindrome (469606964).

It can be divided in two parts, 21710 and 5252, that added together give a palindrome (26962).

The spelling of 217105252 in words is "two hundred seventeen million, one hundred five thousand, two hundred fifty-two".