18684553998 has 32 divisors (see below), whose sum is σ = 40840905600. Its totient is φ = 5651624160.

The previous prime is 18684553991. The next prime is 18684554003. The reversal of 18684553998 is 89935548681.

It is a super-2 number, since 2×18684553998² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18684553991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 222673 + ... + 294876.

It is an arithmetic number, because the mean of its divisors is an integer number (1276278300).

Almost surely, 2^18684553998 is an apocalyptic number.

18684553998 is an abundant number, since it is smaller than the sum of its proper divisors (22156351602).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18684553998 is a wasteful number, since it uses less digits than its factorization.

18684553998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 518112.

The product of its digits is 74649600, while the sum is 66.

The spelling of 18684553998 in words is "eighteen billion, six hundred eighty-four million, five hundred fifty-three thousand, nine hundred ninety-eight".