18208381816 has 16 divisors (see below), whose sum is σ = 34168879800. Its totient is φ = 9096680544.

The previous prime is 18208381787. The next prime is 18208381847. The reversal of 18208381816 is 61818380281.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 928486 + ... + 947893.

Almost surely, 2^18208381816 is an apocalyptic number.

It is an amenable number.

18208381816 is a deficient number, since it is larger than the sum of its proper divisors (15960497984).

18208381816 is a wasteful number, since it uses less digits than its factorization.

18208381816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1877598 (or 1877594 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 46.

The spelling of 18208381816 in words is "eighteen billion, two hundred eight million, three hundred eighty-one thousand, eight hundred sixteen".