638696 has 16 divisors (see below), whose sum is σ = 1239300. Its totient is φ = 308224.

The previous prime is 638689. The next prime is 638699. The reversal of 638696 is 696836.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 592900 + 45796 = 770^2 + 214^2 .

It is not an unprimeable number, because it can be changed into a prime (638699) by changing a digit.

638696 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1145 + ... + 1608.

2⁶³⁸⁶⁹⁶ is an apocalyptic number.

It is an amenable number.

638696 is a deficient number, since it is larger than the sum of its proper divisors (600604).

638696 is a wasteful number, since it uses less digits than its factorization.

638696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2788 (or 2784 counting only the distinct ones).

The product of its digits is 46656, while the sum is 38.

The square root of 638696 is about 799.1845844359. The cubic root of 638696 is about 86.1188189963.

The spelling of 638696 in words is "six hundred thirty-eight thousand, six hundred ninety-six".