18281194378 has 4 divisors (see below), whose sum is σ = 27421791570. Its totient is φ = 9140597188.

The previous prime is 18281194369. The next prime is 18281194387. The reversal of 18281194378 is 87349118281.

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

It is an interprime number because it is at equal distance from previous prime (18281194369) and next prime (18281194387).

It can be written as a sum of positive squares in only one way, i.e., 11350132369 + 6931062009 = 106537^2 + 83253^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4570298593 + ... + 4570298596.

Almost surely, 2^18281194378 is an apocalyptic number.

18281194378 is a deficient number, since it is larger than the sum of its proper divisors (9140597192).

18281194378 is an equidigital number, since it uses as much as digits as its factorization.

18281194378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9140597191.

The product of its digits is 774144, while the sum is 52.

The spelling of 18281194378 in words is "eighteen billion, two hundred eighty-one million, one hundred ninety-four thousand, three hundred seventy-eight".