638617 has 6 divisors (see below), whose sum is σ = 742938. Its totient is φ = 547344.

The previous prime is 638587. The next prime is 638621. The reversal of 638617 is 716836.

It can be written as a sum of positive squares in only one way, i.e., 571536 + 67081 = 756^2 + 259^2 .

It is not a de Polignac number, because 638617 - 2⁷ = 638489 is a prime.

It is a super-3 number, since 3×638617³ = 781344717952893339, which contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (638117) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6468 + ... + 6565.

It is an arithmetic number, because the mean of its divisors is an integer number (123823).

2⁶³⁸⁶¹⁷ is an apocalyptic number.

It is an amenable number.

638617 is a deficient number, since it is larger than the sum of its proper divisors (104321).

638617 is a wasteful number, since it uses less digits than its factorization.

638617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13047 (or 13040 counting only the distinct ones).

The product of its digits is 6048, while the sum is 31.

The square root of 638617 is about 799.1351575297. The cubic root of 638617 is about 86.1152681849.

The spelling of 638617 in words is "six hundred thirty-eight thousand, six hundred seventeen".