638033285 has 16 divisors (see below), whose sum is σ = 770849904. Its totient is φ = 506967552.

The previous prime is 638033251. The next prime is 638033287. The reversal of 638033285 is 582330836.

It can be written as a sum of positive squares in 8 ways, for example, as 3094081 + 634939204 = 1759^2 + 25198^2 .

It is a cyclic number.

It is not a de Polignac number, because 638033285 - 2⁸ = 638033029 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638033287) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 583199 + ... + 584291.

It is an arithmetic number, because the mean of its divisors is an integer number (48178119).

Almost surely, 2^638033285 is an apocalyptic number.

It is an amenable number.

638033285 is a deficient number, since it is larger than the sum of its proper divisors (132816619).

638033285 is a wasteful number, since it uses less digits than its factorization.

638033285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1784.

The product of its (nonzero) digits is 103680, while the sum is 38.

The square root of 638033285 is about 25259.3207549213. The cubic root of 638033285 is about 860.8902287839.

The spelling of 638033285 in words is "six hundred thirty-eight million, thirty-three thousand, two hundred eighty-five".