68638 has 4 divisors (see below), whose sum is σ = 102960. Its totient is φ = 34318.

The previous prime is 68633. The next prime is 68639. The reversal of 68638 is 83686.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83686 = 2 ⋅41843.

It is a super-2 number, since 2×68638² = 9422350088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17158 + ... + 17161.

It is an arithmetic number, because the mean of its divisors is an integer number (25740).

2⁶⁸⁶³⁸ is an apocalyptic number.

68638 is a deficient number, since it is larger than the sum of its proper divisors (34322).

68638 is a wasteful number, since it uses less digits than its factorization.

68638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34321.

The product of its digits is 6912, while the sum is 31.

The square root of 68638 is about 261.9885493681. The cubic root of 68638 is about 40.9438056250.

The spelling of 68638 in words is "sixty-eight thousand, six hundred thirty-eight".