638489071 has 8 divisors (see below), whose sum is σ = 702019584. Its totient is φ = 575872920.

The previous prime is 638489041. The next prime is 638489087. The reversal of 638489071 is 170984836.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 638489071 - 2⁷ = 638488943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638489041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 227125 + ... + 229918.

It is an arithmetic number, because the mean of its divisors is an integer number (87752448).

Almost surely, 2^638489071 is an apocalyptic number.

638489071 is a deficient number, since it is larger than the sum of its proper divisors (63530513).

638489071 is a wasteful number, since it uses less digits than its factorization.

638489071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457181.

The product of its (nonzero) digits is 290304, while the sum is 46.

The square root of 638489071 is about 25268.3412791580. The cubic root of 638489071 is about 861.0951754150.

The spelling of 638489071 in words is "six hundred thirty-eight million, four hundred eighty-nine thousand, seventy-one".