139931 has 4 divisors (see below), whose sum is σ = 152664. Its totient is φ = 127200.

The previous prime is 139921. The next prime is 139939.

139931 = 69² + 70² + ... + 90².

139931 is nontrivially palindromic in base 10.

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 139931 - 2¹⁴ = 123547 is a prime.

It is a super-2 number, since 2×139931² = 39161369522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 139931.

It is not an unprimeable number, because it can be changed into a prime (139939) 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, 6350 + ... + 6371.

It is an arithmetic number, because the mean of its divisors is an integer number (38166).

2¹³⁹⁹³¹ is an apocalyptic number.

139931 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

139931 is a deficient number, since it is larger than the sum of its proper divisors (12733).

139931 is a wasteful number, since it uses less digits than its factorization.

139931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12732.

The product of its digits is 729, while the sum is 26.

The square root of 139931 is about 374.0735221851. The cubic root of 139931 is about 51.9164090907.

The spelling of 139931 in words is "one hundred thirty-nine thousand, nine hundred thirty-one".