194143809 has 8 divisors (see below), whose sum is σ = 258996640. Its totient is φ = 129360096.

The previous prime is 194143787. The next prime is 194143813. The reversal of 194143809 is 908341491.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 194143809 - 2¹² = 194139713 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (194143819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10324 + ... + 22245.

It is an arithmetic number, because the mean of its divisors is an integer number (32374580).

Almost surely, 2^194143809 is an apocalyptic number.

It is an amenable number.

194143809 is a deficient number, since it is larger than the sum of its proper divisors (64852831).

194143809 is a wasteful number, since it uses less digits than its factorization.

194143809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34559.

The product of its (nonzero) digits is 31104, while the sum is 39.

The square root of 194143809 is about 13933.5497630719. The cubic root of 194143809 is about 579.0390439038.

The spelling of 194143809 in words is "one hundred ninety-four million, one hundred forty-three thousand, eight hundred nine".