139945 has 8 divisors (see below), whose sum is σ = 180936. Its totient is φ = 103296.

The previous prime is 139943. The next prime is 139967. The reversal of 139945 is 549931.

It can be written as a sum of positive squares in 4 ways, for example, as 2304 + 137641 = 48^2 + 371^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 139945 - 2¹ = 139943 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 (139943) 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 7 ways as a sum of consecutive naturals, for example, 1012 + ... + 1141.

It is an arithmetic number, because the mean of its divisors is an integer number (22617).

2¹³⁹⁹⁴⁵ is an apocalyptic number.

It is an amenable number.

139945 is a deficient number, since it is larger than the sum of its proper divisors (40991).

139945 is a wasteful number, since it uses less digits than its factorization.

139945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2171.

The product of its digits is 4860, while the sum is 31.

The square root of 139945 is about 374.0922346160. The cubic root of 139945 is about 51.9181404332.

It can be divided in two parts, 1399 and 45, that added together give a square (1444 = 38²).

The spelling of 139945 in words is "one hundred thirty-nine thousand, nine hundred forty-five".