139971 has 16 divisors (see below), whose sum is σ = 208544. Its totient is φ = 82944.

The previous prime is 139969. The next prime is 139981. The reversal of 139971 is 179931.

139971 is nontrivially palindromic in base 6.

It is not a de Polignac number, because 139971 - 2¹ = 139969 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1395 + ... + 1491.

It is an arithmetic number, because the mean of its divisors is an integer number (13034).

2¹³⁹⁹⁷¹ is an apocalyptic number.

139971 is a deficient number, since it is larger than the sum of its proper divisors (68573).

139971 is a wasteful number, since it uses less digits than its factorization.

139971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150.

The product of its digits is 1701, while the sum is 30.

The square root of 139971 is about 374.1269837903. The cubic root of 139971 is about 51.9213554774.

The spelling of 139971 in words is "one hundred thirty-nine thousand, nine hundred seventy-one".