208573009 has 2 divisors, whose sum is σ = 208573010. Its totient is φ = 208573008.

The previous prime is 208572961. The next prime is 208573019. The reversal of 208573009 is 900375802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106502400 + 102070609 = 10320^2 + 10103^2 .

It is a cyclic number.

It is not a de Polignac number, because 208573009 - 2¹⁹ = 208048721 is a prime.

It is not a weakly prime, because it can be changed into another prime (208573019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104286504 + 104286505.

It is an arithmetic number, because the mean of its divisors is an integer number (104286505).

Almost surely, 2^208573009 is an apocalyptic number.

It is an amenable number.

208573009 is a deficient number, since it is larger than the sum of its proper divisors (1).

208573009 is an equidigital number, since it uses as much as digits as its factorization.

208573009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 208573009 is about 14442.0569518334. The cubic root of 208573009 is about 593.0427971656.

The spelling of 208573009 in words is "two hundred eight million, five hundred seventy-three thousand, nine".