638608441 has 2 divisors, whose sum is σ = 638608442. Its totient is φ = 638608440.

The previous prime is 638608427. The next prime is 638608459. The reversal of 638608441 is 144806836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 510579216 + 128029225 = 22596^2 + 11315^2 .

It is a cyclic number.

It is not a de Polignac number, because 638608441 - 2¹¹ = 638606393 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 638608394 and 638608403.

It is not a weakly prime, because it can be changed into another prime (638608541) 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, 319304220 + 319304221.

It is an arithmetic number, because the mean of its divisors is an integer number (319304221).

Almost surely, 2^638608441 is an apocalyptic number.

It is an amenable number.

638608441 is a deficient number, since it is larger than the sum of its proper divisors (1).

638608441 is an equidigital number, since it uses as much as digits as its factorization.

638608441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 638608441 is about 25270.7032153836. The cubic root of 638608441 is about 861.1488346608.

The spelling of 638608441 in words is "six hundred thirty-eight million, six hundred eight thousand, four hundred forty-one".