638269 has 2 divisors, whose sum is σ = 638270. Its totient is φ = 638268.

The previous prime is 638263. The next prime is 638303. The reversal of 638269 is 962836.

It is a happy number.

It is an a-pointer prime, because the next prime (638303) can be obtained adding 638269 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 592900 + 45369 = 770^2 + 213^2 .

It is a cyclic number.

It is not a de Polignac number, because 638269 - 2¹⁷ = 507197 is a prime.

It is a super-2 number, since 2×638269² = 814774632722, which contains 22 as substring.

638269 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638263) 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, 319134 + 319135.

It is an arithmetic number, because the mean of its divisors is an integer number (319135).

2⁶³⁸²⁶⁹ is an apocalyptic number.

It is an amenable number.

638269 is a deficient number, since it is larger than the sum of its proper divisors (1).

638269 is an equidigital number, since it uses as much as digits as its factorization.

638269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 34.

The square root of 638269 is about 798.9173924756. The cubic root of 638269 is about 86.0996231486.

The spelling of 638269 in words is "six hundred thirty-eight thousand, two hundred sixty-nine".