212120109989 has 2 divisors, whose sum is σ = 212120109990. Its totient is φ = 212120109988.

The previous prime is 212120109977. The next prime is 212120110001. The reversal of 212120109989 is 989901021212.

It is a balanced prime because it is at equal distance from previous prime (212120109977) and next prime (212120110001).

It can be written as a sum of positive squares in only one way, i.e., 206426652964 + 5693457025 = 454342^2 + 75455^2 .

It is a cyclic number.

It is not a de Polignac number, because 212120109989 - 2¹⁶ = 212120044453 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212120108989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060054994 + 106060054995.

It is an arithmetic number, because the mean of its divisors is an integer number (106060054995).

Almost surely, 2^212120109989 is an apocalyptic number.

It is an amenable number.

212120109989 is a deficient number, since it is larger than the sum of its proper divisors (1).

212120109989 is an equidigital number, since it uses as much as digits as its factorization.

212120109989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 44.

The spelling of 212120109989 in words is "two hundred twelve billion, one hundred twenty million, one hundred nine thousand, nine hundred eighty-nine".