210111020909 has 2 divisors, whose sum is σ = 210111020910. Its totient is φ = 210111020908.

The previous prime is 210111020887. The next prime is 210111021007. The reversal of 210111020909 is 909020111012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 193520808100 + 16590212809 = 439910^2 + 128803^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210111020909 is a prime.

It is a super-2 number, since 2×210111020909² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210111020809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105055510454 + 105055510455.

It is an arithmetic number, because the mean of its divisors is an integer number (105055510455).

Almost surely, 2^210111020909 is an apocalyptic number.

It is an amenable number.

210111020909 is a deficient number, since it is larger than the sum of its proper divisors (1).

210111020909 is an equidigital number, since it uses as much as digits as its factorization.

210111020909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 26.

The spelling of 210111020909 in words is "two hundred ten billion, one hundred eleven million, twenty thousand, nine hundred nine".