378173809 has 4 divisors (see below), whose sum is σ = 407264116. Its totient is φ = 349083504.

The previous prime is 378173779. The next prime is 378173821. The reversal of 378173809 is 908371873.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 908371873 = 24329 ⋅37337.

It can be written as a sum of positive squares in 2 ways, for example, as 101949409 + 276224400 = 10097^2 + 16620^2 .

It is a cyclic number.

It is not a de Polignac number, because 378173809 - 2¹⁵ = 378141041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (378173879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14545134 + ... + 14545159.

It is an arithmetic number, because the mean of its divisors is an integer number (101816029).

Almost surely, 2^378173809 is an apocalyptic number.

It is an amenable number.

378173809 is a deficient number, since it is larger than the sum of its proper divisors (29090307).

378173809 is a wasteful number, since it uses less digits than its factorization.

378173809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29090306.

The product of its (nonzero) digits is 254016, while the sum is 46.

The square root of 378173809 is about 19446.6914666737. The cubic root of 378173809 is about 723.1534835455.

The spelling of 378173809 in words is "three hundred seventy-eight million, one hundred seventy-three thousand, eight hundred nine".