211100001989 has 2 divisors, whose sum is σ = 211100001990. Its totient is φ = 211100001988.

The previous prime is 211100001971. The next prime is 211100001997. The reversal of 211100001989 is 989100001112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137480033089 + 73619968900 = 370783^2 + 271330^2 .

It is a cyclic number.

It is not a de Polignac number, because 211100001989 - 2¹² = 211099997893 is a prime.

It is a super-2 number, since 2×211100001989² (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 (211100001389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105550000994 + 105550000995.

It is an arithmetic number, because the mean of its divisors is an integer number (105550000995).

Almost surely, 2^211100001989 is an apocalyptic number.

It is an amenable number.

211100001989 is a deficient number, since it is larger than the sum of its proper divisors (1).

211100001989 is an equidigital number, since it uses as much as digits as its factorization.

211100001989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 32.

The spelling of 211100001989 in words is "two hundred eleven billion, one hundred million, one thousand, nine hundred eighty-nine".