211121020109 has 2 divisors, whose sum is σ = 211121020110. Its totient is φ = 211121020108.

The previous prime is 211121020087. The next prime is 211121020157. The reversal of 211121020109 is 901020121112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209692558084 + 1428462025 = 457922^2 + 37795^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211121020109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211121022109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105560510054 + 105560510055.

It is an arithmetic number, because the mean of its divisors is an integer number (105560510055).

Almost surely, 2^211121020109 is an apocalyptic number.

It is an amenable number.

211121020109 is a deficient number, since it is larger than the sum of its proper divisors (1).

211121020109 is an equidigital number, since it uses as much as digits as its factorization.

211121020109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 211121020109 in words is "two hundred eleven billion, one hundred twenty-one million, twenty thousand, one hundred nine".