18640921418 has 8 divisors (see below), whose sum is σ = 31955865312. Its totient is φ = 7988966316.

The previous prime is 18640921417. The next prime is 18640921423. The reversal of 18640921418 is 81412904681.

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

It is a super-2 number, since 2×18640921418² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18640921417) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 665747180 + ... + 665747207.

It is an arithmetic number, because the mean of its divisors is an integer number (3994483164).

Almost surely, 2^18640921418 is an apocalyptic number.

18640921418 is a deficient number, since it is larger than the sum of its proper divisors (13314943894).

18640921418 is a wasteful number, since it uses less digits than its factorization.

18640921418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331494396.

The product of its (nonzero) digits is 110592, while the sum is 44.

The spelling of 18640921418 in words is "eighteen billion, six hundred forty million, nine hundred twenty-one thousand, four hundred eighteen".