212021223109 has 2 divisors, whose sum is σ = 212021223110. Its totient is φ = 212021223108.

The previous prime is 212021223107. The next prime is 212021223157. The reversal of 212021223109 is 901322120212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 206754818209 + 5266404900 = 454703^2 + 72570^2 .

It is a cyclic number.

It is not a de Polignac number, because 212021223109 - 2¹ = 212021223107 is a prime.

Together with 212021223107, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212021223107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106010611554 + 106010611555.

It is an arithmetic number, because the mean of its divisors is an integer number (106010611555).

Almost surely, 2^212021223109 is an apocalyptic number.

It is an amenable number.

212021223109 is a deficient number, since it is larger than the sum of its proper divisors (1).

212021223109 is an equidigital number, since it uses as much as digits as its factorization.

212021223109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The spelling of 212021223109 in words is "two hundred twelve billion, twenty-one million, two hundred twenty-three thousand, one hundred nine".