209141892809 has 2 divisors, whose sum is σ = 209141892810. Its totient is φ = 209141892808.

The previous prime is 209141892781. The next prime is 209141892821. The reversal of 209141892809 is 908298141902.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195764657209 + 13377235600 = 442453^2 + 115660^2 .

It is a cyclic number.

It is not a de Polignac number, because 209141892809 - 2²⁰ = 209140844233 is a prime.

It is not a weakly prime, because it can be changed into another prime (209141898809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104570946404 + 104570946405.

It is an arithmetic number, because the mean of its divisors is an integer number (104570946405).

Almost surely, 2^209141892809 is an apocalyptic number.

It is an amenable number.

209141892809 is a deficient number, since it is larger than the sum of its proper divisors (1).

209141892809 is an equidigital number, since it uses as much as digits as its factorization.

209141892809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 746496, while the sum is 53.

The spelling of 209141892809 in words is "two hundred nine billion, one hundred forty-one million, eight hundred ninety-two thousand, eight hundred nine".