638450 has 18 divisors (see below), whose sum is σ = 1198119. Its totient is φ = 253120.

The previous prime is 638437. The next prime is 638453. The reversal of 638450 is 54836.

It can be written as a sum of positive squares in 5 ways, for example, as 49 + 638401 = 7^2 + 799^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=565.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638453) by changing a digit.

638450 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 in 8 ways as a sum of consecutive naturals, for example, 5594 + ... + 5706.

2⁶³⁸⁴⁵⁰ is an apocalyptic number.

638450 is a deficient number, since it is larger than the sum of its proper divisors (559669).

638450 is a wasteful number, since it uses less digits than its factorization.

638450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 638450 is about 799.0306627408. The cubic root of 638450 is about 86.1077610752.

The spelling of 638450 in words is "six hundred thirty-eight thousand, four hundred fifty".