208447997 has 2 divisors, whose sum is σ = 208447998. Its totient is φ = 208447996.

The previous prime is 208447963. The next prime is 208448017. The reversal of 208447997 is 799744802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 191711716 + 16736281 = 13846^2 + 4091^2 .

It is a cyclic number.

It is not a de Polignac number, because 208447997 - 2⁶ = 208447933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208447927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104223998 + 104223999.

It is an arithmetic number, because the mean of its divisors is an integer number (104223999).

Almost surely, 2^208447997 is an apocalyptic number.

It is an amenable number.

208447997 is a deficient number, since it is larger than the sum of its proper divisors (1).

208447997 is an equidigital number, since it uses as much as digits as its factorization.

208447997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1016064, while the sum is 50.

The square root of 208447997 is about 14437.7282492780. The cubic root of 208447997 is about 592.9242898488.

The spelling of 208447997 in words is "two hundred eight million, four hundred forty-seven thousand, nine hundred ninety-seven".