18868638973 has 2 divisors, whose sum is σ = 18868638974. Its totient is φ = 18868638972.

The previous prime is 18868638953. The next prime is 18868638977. The reversal of 18868638973 is 37983686881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18790103929 + 78535044 = 137077^2 + 8862^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18868638973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18868638899 and 18868638908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18868638977) 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 as a sum of consecutive naturals, namely, 9434319486 + 9434319487.

It is an arithmetic number, because the mean of its divisors is an integer number (9434319487).

Almost surely, 2^18868638973 is an apocalyptic number.

It is an amenable number.

18868638973 is a deficient number, since it is larger than the sum of its proper divisors (1).

18868638973 is an equidigital number, since it uses as much as digits as its factorization.

18868638973 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 83607552, while the sum is 67.

The spelling of 18868638973 in words is "eighteen billion, eight hundred sixty-eight million, six hundred thirty-eight thousand, nine hundred seventy-three".