18780023818 has 8 divisors (see below), whose sum is σ = 28172692548. Its totient is φ = 9389126304.

The previous prime is 18780023797. The next prime is 18780023819. The reversal of 18780023818 is 81832008781.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18773658289 + 6365529 = 137017^2 + 2523^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (18780023819) 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, 415971 + ... + 458902.

Almost surely, 2^18780023818 is an apocalyptic number.

18780023818 is a deficient number, since it is larger than the sum of its proper divisors (9392668730).

18780023818 is a wasteful number, since it uses less digits than its factorization.

18780023818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885608.

The product of its (nonzero) digits is 172032, while the sum is 46.

The spelling of 18780023818 in words is "eighteen billion, seven hundred eighty million, twenty-three thousand, eight hundred eighteen".