212111220109 has 2 divisors, whose sum is σ = 212111220110. Its totient is φ = 212111220108.

The previous prime is 212111220077. The next prime is 212111220121. The reversal of 212111220109 is 901022111212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209883096900 + 2228123209 = 458130^2 + 47203^2 .

It is a cyclic number.

It is not a de Polignac number, because 212111220109 - 2⁵ = 212111220077 is a prime.

It is a super-2 number, since 2×212111220109² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 212111220109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212117220109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106055610054 + 106055610055.

It is an arithmetic number, because the mean of its divisors is an integer number (106055610055).

Almost surely, 2^212111220109 is an apocalyptic number.

It is an amenable number.

212111220109 is a deficient number, since it is larger than the sum of its proper divisors (1).

212111220109 is an equidigital number, since it uses as much as digits as its factorization.

212111220109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 212111220109 in words is "two hundred twelve billion, one hundred eleven million, two hundred twenty thousand, one hundred nine".