638330065 has 4 divisors (see below), whose sum is σ = 765996084. Its totient is φ = 510664048.

The previous prime is 638330053. The next prime is 638330081. The reversal of 638330065 is 560033836.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 120494529 + 517835536 = 10977^2 + 22756^2 .

It is a cyclic number.

It is not a de Polignac number, because 638330065 - 2¹⁷ = 638198993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638330065.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 63833002 + ... + 63833011.

It is an arithmetic number, because the mean of its divisors is an integer number (191499021).

Almost surely, 2^638330065 is an apocalyptic number.

It is an amenable number.

638330065 is a deficient number, since it is larger than the sum of its proper divisors (127666019).

638330065 is a wasteful number, since it uses less digits than its factorization.

638330065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127666018.

The product of its (nonzero) digits is 38880, while the sum is 34.

The square root of 638330065 is about 25265.1947350500. The cubic root of 638330065 is about 861.0236885913.

The spelling of 638330065 in words is "six hundred thirty-eight million, three hundred thirty thousand, sixty-five".