211010001809 has 2 divisors, whose sum is σ = 211010001810. Its totient is φ = 211010001808.

The previous prime is 211010001793. The next prime is 211010001889. The reversal of 211010001809 is 908100010112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 206885793409 + 4124208400 = 454847^2 + 64220^2 .

It is a cyclic number.

It is not a de Polignac number, because 211010001809 - 2⁴ = 211010001793 is a prime.

It is not a weakly prime, because it can be changed into another prime (211010001889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105505000904 + 105505000905.

It is an arithmetic number, because the mean of its divisors is an integer number (105505000905).

Almost surely, 2^211010001809 is an apocalyptic number.

It is an amenable number.

211010001809 is a deficient number, since it is larger than the sum of its proper divisors (1).

211010001809 is an equidigital number, since it uses as much as digits as its factorization.

211010001809 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 23.

The spelling of 211010001809 in words is "two hundred eleven billion, ten million, one thousand, eight hundred nine".