139001 has 4 divisors (see below), whose sum is σ = 140532. Its totient is φ = 137472.

The previous prime is 138977. The next prime is 139021. The reversal of 139001 is 100931.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 90601 + 48400 = 301^2 + 220^2 .

It is a cyclic number.

It is not a de Polignac number, because 139001 - 2⁶ = 138937 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 620 + ... + 813.

It is an arithmetic number, because the mean of its divisors is an integer number (35133).

2¹³⁹⁰⁰¹ is an apocalyptic number.

It is an amenable number.

139001 is a deficient number, since it is larger than the sum of its proper divisors (1531).

139001 is an equidigital number, since it uses as much as digits as its factorization.

139001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1530.

The product of its (nonzero) digits is 27, while the sum is 14.

The square root of 139001 is about 372.8283787482. The cubic root of 139001 is about 51.8011388966.

Adding to 139001 its reverse (100931), we get a palindrome (239932).

The spelling of 139001 in words is "one hundred thirty-nine thousand, one".