1818384638 has 16 divisors (see below), whose sum is σ = 3117882240. Its totient is φ = 779144856.

The previous prime is 1818384629. The next prime is 1818384649. The reversal of 1818384638 is 8364838181.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76373 + ... + 97311.

It is an arithmetic number, because the mean of its divisors is an integer number (194867640).

Almost surely, 2^1818384638 is an apocalyptic number.

1818384638 is a deficient number, since it is larger than the sum of its proper divisors (1299497602).

1818384638 is a wasteful number, since it uses less digits than its factorization.

1818384638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27151.

The product of its digits is 884736, while the sum is 50.

The square root of 1818384638 is about 42642.5214779802. The cubic root of 1818384638 is about 1220.5678262419.

The spelling of 1818384638 in words is "one billion, eight hundred eighteen million, three hundred eighty-four thousand, six hundred thirty-eight".