194025409 has 4 divisors (see below), whose sum is σ = 195030916. Its totient is φ = 193019904.

The previous prime is 194025389. The next prime is 194025427. The reversal of 194025409 is 904520491.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 904520491 = 7 ⋅129217213.

It can be written as a sum of positive squares in 2 ways, for example, as 58186384 + 135839025 = 7628^2 + 11655^2 .

It is a cyclic number.

It is not a de Polignac number, because 194025409 - 2¹³ = 194017217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (194025509) 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 in 3 ways as a sum of consecutive naturals, for example, 502464 + ... + 502849.

It is an arithmetic number, because the mean of its divisors is an integer number (48757729).

Almost surely, 2^194025409 is an apocalyptic number.

It is an amenable number.

194025409 is a deficient number, since it is larger than the sum of its proper divisors (1005507).

194025409 is a wasteful number, since it uses less digits than its factorization.

194025409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005506.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 194025409 is about 13929.3003772623. The cubic root of 194025409 is about 578.9213095899.

The spelling of 194025409 in words is "one hundred ninety-four million, twenty-five thousand, four hundred nine".