18638913833 has 2 divisors, whose sum is σ = 18638913834. Its totient is φ = 18638913832.

The previous prime is 18638913829. The next prime is 18638913863. The reversal of 18638913833 is 33831983681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18104240704 + 534673129 = 134552^2 + 23123^2 .

It is a cyclic number.

It is not a de Polignac number, because 18638913833 - 2² = 18638913829 is a prime.

It is not a weakly prime, because it can be changed into another prime (18638913863) 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, 9319456916 + 9319456917.

It is an arithmetic number, because the mean of its divisors is an integer number (9319456917).

Almost surely, 2^18638913833 is an apocalyptic number.

It is an amenable number.

18638913833 is a deficient number, since it is larger than the sum of its proper divisors (1).

18638913833 is an equidigital number, since it uses as much as digits as its factorization.

18638913833 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 53.

The spelling of 18638913833 in words is "eighteen billion, six hundred thirty-eight million, nine hundred thirteen thousand, eight hundred thirty-three".