638112133 has 2 divisors, whose sum is σ = 638112134. Its totient is φ = 638112132.

The previous prime is 638112113. The next prime is 638112157. The reversal of 638112133 is 331211836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 448719489 + 189392644 = 21183^2 + 13762^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638112133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638112113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319056066 + 319056067.

It is an arithmetic number, because the mean of its divisors is an integer number (319056067).

Almost surely, 2^638112133 is an apocalyptic number.

It is an amenable number.

638112133 is a deficient number, since it is larger than the sum of its proper divisors (1).

638112133 is an equidigital number, since it uses as much as digits as its factorization.

638112133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 28.

The square root of 638112133 is about 25260.8814770981. The cubic root of 638112133 is about 860.9256901923.

Adding to 638112133 its reverse (331211836), we get a palindrome (969323969).

The spelling of 638112133 in words is "six hundred thirty-eight million, one hundred twelve thousand, one hundred thirty-three".