139631 has 4 divisors (see below), whose sum is σ = 147000. Its totient is φ = 132264.

The previous prime is 139627. The next prime is 139661. The reversal of 139631 is 136931.

139631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 136931 = 149 ⋅919.

It is a cyclic number.

It is not a de Polignac number, because 139631 - 2² = 139627 is a prime.

It is a super-2 number, since 2×139631² = 38993632322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 139597 and 139606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3656 + ... + 3693.

It is an arithmetic number, because the mean of its divisors is an integer number (36750).

2¹³⁹⁶³¹ is an apocalyptic number.

139631 is a deficient number, since it is larger than the sum of its proper divisors (7369).

139631 is an equidigital number, since it uses as much as digits as its factorization.

139631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7368.

The product of its digits is 486, while the sum is 23.

The square root of 139631 is about 373.6723163415. The cubic root of 139631 is about 51.8792811099.

The spelling of 139631 in words is "one hundred thirty-nine thousand, six hundred thirty-one".