212605121 has 2 divisors, whose sum is σ = 212605122. Its totient is φ = 212605120.

The previous prime is 212605109. The next prime is 212605157. The reversal of 212605121 is 121506212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108972721 + 103632400 = 10439^2 + 10180^2 .

It is a cyclic number.

It is not a de Polignac number, because 212605121 - 2¹⁰ = 212604097 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 212605093 and 212605102.

It is not a weakly prime, because it can be changed into another prime (212605171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106302560 + 106302561.

It is an arithmetic number, because the mean of its divisors is an integer number (106302561).

Almost surely, 2^212605121 is an apocalyptic number.

It is an amenable number.

212605121 is a deficient number, since it is larger than the sum of its proper divisors (1).

212605121 is an equidigital number, since it uses as much as digits as its factorization.

212605121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 212605121 is about 14580.9849118638. The cubic root of 212605121 is about 596.8399798574.

The spelling of 212605121 in words is "two hundred twelve million, six hundred five thousand, one hundred twenty-one".