638474517 has 12 divisors (see below), whose sum is σ = 939642444. Its totient is φ = 417618240.

The previous prime is 638474513. The next prime is 638474531. The reversal of 638474517 is 715474836.

638474517 is a `hidden beast` number, since 63 + 8 + 4 + 74 + 517 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 348419556 + 290054961 = 18666^2 + 17031^2 .

It is not a de Polignac number, because 638474517 - 2² = 638474513 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638474513) 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 in 11 ways as a sum of consecutive naturals, for example, 668784 + ... + 669737.

It is an arithmetic number, because the mean of its divisors is an integer number (78303537).

Almost surely, 2^638474517 is an apocalyptic number.

It is an amenable number.

638474517 is a deficient number, since it is larger than the sum of its proper divisors (301167927).

638474517 is a wasteful number, since it uses less digits than its factorization.

638474517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338580 (or 1338577 counting only the distinct ones).

The product of its digits is 564480, while the sum is 45.

The square root of 638474517 is about 25268.0532886885. The cubic root of 638474517 is about 861.0886326382.

The spelling of 638474517 in words is "six hundred thirty-eight million, four hundred seventy-four thousand, five hundred seventeen".