289878409 has 2 divisors, whose sum is σ = 289878410. Its totient is φ = 289878408.

The previous prime is 289878371. The next prime is 289878439. The reversal of 289878409 is 904878982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 170041600 + 119836809 = 13040^2 + 10947^2 .

It is a cyclic number.

It is not a de Polignac number, because 289878409 - 2¹⁵ = 289845641 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 289878409.

It is not a weakly prime, because it can be changed into another prime (289878439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 144939204 + 144939205.

It is an arithmetic number, because the mean of its divisors is an integer number (144939205).

Almost surely, 2^289878409 is an apocalyptic number.

It is an amenable number.

289878409 is a deficient number, since it is larger than the sum of its proper divisors (1).

289878409 is an equidigital number, since it uses as much as digits as its factorization.

289878409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2322432, while the sum is 55.

The square root of 289878409 is about 17025.8159569520. The cubic root of 289878409 is about 661.8180733981.

The spelling of 289878409 in words is "two hundred eighty-nine million, eight hundred seventy-eight thousand, four hundred nine".