378193666 has 4 divisors (see below), whose sum is σ = 567290502. Its totient is φ = 189096832.

The previous prime is 378193661. The next prime is 378193667. The reversal of 378193666 is 666391873.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 377330625 + 863041 = 19425^2 + 929^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (378193661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94548415 + ... + 94548418.

Almost surely, 2^378193666 is an apocalyptic number.

378193666 is a deficient number, since it is larger than the sum of its proper divisors (189096836).

378193666 is a wasteful number, since it uses less digits than its factorization.

378193666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189096835.

The product of its digits is 979776, while the sum is 49.

The square root of 378193666 is about 19447.2020095437. The cubic root of 378193666 is about 723.1661403425.

The spelling of 378193666 in words is "three hundred seventy-eight million, one hundred ninety-three thousand, six hundred sixty-six".