194196409 has 6 divisors (see below), whose sum is σ = 213455690. Its totient is φ = 176542080.

The previous prime is 194196391. The next prime is 194196421. The reversal of 194196409 is 904691491.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 169911225 + 24285184 = 13035^2 + 4928^2 .

It is not a de Polignac number, because 194196409 - 2¹¹ = 194194361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (194196439) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 802344 + ... + 802585.

Almost surely, 2^194196409 is an apocalyptic number.

It is an amenable number.

194196409 is a deficient number, since it is larger than the sum of its proper divisors (19259281).

194196409 is a wasteful number, since it uses less digits than its factorization.

194196409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1604951 (or 1604940 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 194196409 is about 13935.4371657297. The cubic root of 194196409 is about 579.0913328121.

The spelling of 194196409 in words is "one hundred ninety-four million, one hundred ninety-six thousand, four hundred nine".