638283761 has 2 divisors, whose sum is σ = 638283762. Its totient is φ = 638283760.

The previous prime is 638283733. The next prime is 638283817. The reversal of 638283761 is 167382836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 539400625 + 98883136 = 23225^2 + 9944^2 .

It is a cyclic number.

It is not a de Polignac number, because 638283761 - 2⁶ = 638283697 is a prime.

It is not a weakly prime, because it can be changed into another prime (638283721) 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, 319141880 + 319141881.

It is an arithmetic number, because the mean of its divisors is an integer number (319141881).

Almost surely, 2^638283761 is an apocalyptic number.

It is an amenable number.

638283761 is a deficient number, since it is larger than the sum of its proper divisors (1).

638283761 is an equidigital number, since it uses as much as digits as its factorization.

638283761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 44.

The square root of 638283761 is about 25264.2783589795. The cubic root of 638283761 is about 861.0028687432.

The spelling of 638283761 in words is "six hundred thirty-eight million, two hundred eighty-three thousand, seven hundred sixty-one".