212005217 has 2 divisors, whose sum is σ = 212005218. Its totient is φ = 212005216.

The previous prime is 212005193. The next prime is 212005243. The reversal of 212005217 is 712500212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166900561 + 45104656 = 12919^2 + 6716^2 .

It is a cyclic number.

It is not a de Polignac number, because 212005217 - 2²² = 207810913 is a prime.

It is not a weakly prime, because it can be changed into another prime (212005267) by changing a digit.

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 as a sum of consecutive naturals, namely, 106002608 + 106002609.

It is an arithmetic number, because the mean of its divisors is an integer number (106002609).

Almost surely, 2^212005217 is an apocalyptic number.

It is an amenable number.

212005217 is a deficient number, since it is larger than the sum of its proper divisors (1).

212005217 is an equidigital number, since it uses as much as digits as its factorization.

212005217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 212005217 is about 14560.3989299744. The cubic root of 212005217 is about 596.2780868620.

Adding to 212005217 its reverse (712500212), we get a palindrome (924505429).

The spelling of 212005217 in words is "two hundred twelve million, five thousand, two hundred seventeen".