18679773988 has 6 divisors (see below), whose sum is σ = 32689604486. Its totient is φ = 9339886992.

The previous prime is 18679773977. The next prime is 18679773997. The reversal of 18679773988 is 88937797681.

It can be written as a sum of positive squares in only one way, i.e., 9549589284 + 9130184704 = 97722^2 + 95552^2 .

It is a super-2 number, since 2×18679773988² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18679773988.

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 as a sum of consecutive naturals, namely, 2334971745 + ... + 2334971752.

Almost surely, 2^18679773988 is an apocalyptic number.

It is an amenable number.

18679773988 is a deficient number, since it is larger than the sum of its proper divisors (14009830498).

18679773988 is a wasteful number, since it uses less digits than its factorization.

18679773988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4669943501 (or 4669943499 counting only the distinct ones).

The product of its digits is 256048128, while the sum is 73.

The spelling of 18679773988 in words is "eighteen billion, six hundred seventy-nine million, seven hundred seventy-three thousand, nine hundred eighty-eight".