138993 has 8 divisors (see below), whose sum is σ = 187488. Its totient is φ = 91584.

The previous prime is 138977. The next prime is 139021. The reversal of 138993 is 399831.

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

It is not a de Polignac number, because 138993 - 2⁴ = 138977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138923) 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, 105 + ... + 537.

It is an arithmetic number, because the mean of its divisors is an integer number (23436).

2¹³⁸⁹⁹³ is an apocalyptic number.

It is an amenable number.

138993 is a deficient number, since it is larger than the sum of its proper divisors (48495).

138993 is a wasteful number, since it uses less digits than its factorization.

138993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543.

The product of its digits is 5832, while the sum is 33.

The square root of 138993 is about 372.8176497968. The cubic root of 138993 is about 51.8001450978.

The spelling of 138993 in words is "one hundred thirty-eight thousand, nine hundred ninety-three".