209467889 has 2 divisors, whose sum is σ = 209467890. Its totient is φ = 209467888.

The previous prime is 209467883. The next prime is 209467901. The reversal of 209467889 is 988764902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 168610225 + 40857664 = 12985^2 + 6392^2 .

It is a cyclic number.

It is not a de Polignac number, because 209467889 - 2²⁰ = 208419313 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 209467889.

It is not a weakly prime, because it can be changed into another prime (209467883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104733944 + 104733945.

It is an arithmetic number, because the mean of its divisors is an integer number (104733945).

Almost surely, 2^209467889 is an apocalyptic number.

It is an amenable number.

209467889 is a deficient number, since it is larger than the sum of its proper divisors (1).

209467889 is an equidigital number, since it uses as much as digits as its factorization.

209467889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1741824, while the sum is 53.

The square root of 209467889 is about 14473.0055275330. The cubic root of 209467889 is about 593.8897347351.

The spelling of 209467889 in words is "two hundred nine million, four hundred sixty-seven thousand, eight hundred eighty-nine".