208719961 has 2 divisors, whose sum is σ = 208719962. Its totient is φ = 208719960.

The previous prime is 208719949. The next prime is 208719977. The reversal of 208719961 is 169917802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105575625 + 103144336 = 10275^2 + 10156^2 .

It is a cyclic number.

It is not a de Polignac number, because 208719961 - 2⁹ = 208719449 is a prime.

It is not a weakly prime, because it can be changed into another prime (208719361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104359980 + 104359981.

It is an arithmetic number, because the mean of its divisors is an integer number (104359981).

Almost surely, 2^208719961 is an apocalyptic number.

It is an amenable number.

208719961 is a deficient number, since it is larger than the sum of its proper divisors (1).

208719961 is an equidigital number, since it uses as much as digits as its factorization.

208719961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 43.

The square root of 208719961 is about 14447.1436969389. The cubic root of 208719961 is about 593.1820423575.

The spelling of 208719961 in words is "two hundred eight million, seven hundred nineteen thousand, nine hundred sixty-one".