209420447 has 2 divisors, whose sum is σ = 209420448. Its totient is φ = 209420446.

The previous prime is 209420443. The next prime is 209420459. The reversal of 209420447 is 744024902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 209420447 - 2² = 209420443 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209420443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104710223 + 104710224.

It is an arithmetic number, because the mean of its divisors is an integer number (104710224).

Almost surely, 2^209420447 is an apocalyptic number.

209420447 is a deficient number, since it is larger than the sum of its proper divisors (1).

209420447 is an equidigital number, since it uses as much as digits as its factorization.

209420447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 209420447 is about 14471.3664524122. The cubic root of 209420447 is about 593.8448950156.

The spelling of 209420447 in words is "two hundred nine million, four hundred twenty thousand, four hundred forty-seven".