18765976321 has 2 divisors, whose sum is σ = 18765976322. Its totient is φ = 18765976320.

The previous prime is 18765976319. The next prime is 18765976351. The reversal of 18765976321 is 12367956781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15620000400 + 3145975921 = 124980^2 + 56089^2 .

It is a cyclic number.

It is not a de Polignac number, because 18765976321 - 2¹ = 18765976319 is a prime.

Together with 18765976319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18765976351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9382988160 + 9382988161.

It is an arithmetic number, because the mean of its divisors is an integer number (9382988161).

Almost surely, 2^18765976321 is an apocalyptic number.

It is an amenable number.

18765976321 is a deficient number, since it is larger than the sum of its proper divisors (1).

18765976321 is an equidigital number, since it uses as much as digits as its factorization.

18765976321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3810240, while the sum is 55.

The spelling of 18765976321 in words is "eighteen billion, seven hundred sixty-five million, nine hundred seventy-six thousand, three hundred twenty-one".