208961 has 2 divisors, whose sum is σ = 208962. Its totient is φ = 208960.

The previous prime is 208933. The next prime is 208963. The reversal of 208961 is 169802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 207025 + 1936 = 455^2 + 44^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208961 is a prime.

Together with 208963, it forms a pair of twin primes.

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 208961.

It is not a weakly prime, because it can be changed into another prime (208963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104480 + 104481.

It is an arithmetic number, because the mean of its divisors is an integer number (104481).

2²⁰⁸⁹⁶¹ is an apocalyptic number.

It is an amenable number.

208961 is a deficient number, since it is larger than the sum of its proper divisors (1).

208961 is an equidigital number, since it uses as much as digits as its factorization.

208961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 208961 is about 457.1225218691. The cubic root of 208961 is about 59.3410298759.

The spelling of 208961 in words is "two hundred eight thousand, nine hundred sixty-one".