289877221 has 2 divisors, whose sum is σ = 289877222. Its totient is φ = 289877220.

The previous prime is 289877219. The next prime is 289877297. The reversal of 289877221 is 122778982.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 288150625 + 1726596 = 16975^2 + 1314^2 .

It is a cyclic number.

It is not a de Polignac number, because 289877221 - 2¹ = 289877219 is a prime.

Together with 289877219, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (289877201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 144938610 + 144938611.

It is an arithmetic number, because the mean of its divisors is an integer number (144938611).

Almost surely, 2^289877221 is an apocalyptic number.

It is an amenable number.

289877221 is a deficient number, since it is larger than the sum of its proper divisors (1).

289877221 is an equidigital number, since it uses as much as digits as its factorization.

289877221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 46.

The square root of 289877221 is about 17025.7810687205. The cubic root of 289877221 is about 661.8171692938.

The spelling of 289877221 in words is "two hundred eighty-nine million, eight hundred seventy-seven thousand, two hundred twenty-one".