194948209 has 2 divisors, whose sum is σ = 194948210. Its totient is φ = 194948208.

The previous prime is 194948147. The next prime is 194948219. The reversal of 194948209 is 902849491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147379600 + 47568609 = 12140^2 + 6897^2 .

It is an emirp because it is prime and its reverse (902849491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 194948209 - 2¹¹ = 194946161 is a prime.

It is not a weakly prime, because it can be changed into another prime (194948219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97474104 + 97474105.

It is an arithmetic number, because the mean of its divisors is an integer number (97474105).

Almost surely, 2^194948209 is an apocalyptic number.

It is an amenable number.

194948209 is a deficient number, since it is larger than the sum of its proper divisors (1).

194948209 is an equidigital number, since it uses as much as digits as its factorization.

194948209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 194948209 is about 13962.3855053497. The cubic root of 194948209 is about 579.8376567043.

The spelling of 194948209 in words is "one hundred ninety-four million, nine hundred forty-eight thousand, two hundred nine".