139687 has 4 divisors (see below), whose sum is σ = 143136. Its totient is φ = 136240.

The previous prime is 139681. The next prime is 139697. The reversal of 139687 is 786931.

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

It is a cyclic number.

It is not a de Polignac number, because 139687 - 2¹¹ = 137639 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 (139681) 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, 1663 + ... + 1744.

It is an arithmetic number, because the mean of its divisors is an integer number (35784).

2¹³⁹⁶⁸⁷ is an apocalyptic number.

139687 is a deficient number, since it is larger than the sum of its proper divisors (3449).

139687 is an equidigital number, since it uses as much as digits as its factorization.

139687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3448.

The product of its digits is 9072, while the sum is 34.

The square root of 139687 is about 373.7472407925. The cubic root of 139687 is about 51.8862157004.

The spelling of 139687 in words is "one hundred thirty-nine thousand, six hundred eighty-seven".