139966 has 8 divisors (see below), whose sum is σ = 214560. Its totient is φ = 68448.

The previous prime is 139943. The next prime is 139967. The reversal of 139966 is 669931.

139966 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139967) 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, 651 + ... + 838.

It is an arithmetic number, because the mean of its divisors is an integer number (26820).

139966 is a Friedman number, since it can be written as 9/9+3*(6^6-1), using all its digits and the basic arithmetic operations.

2¹³⁹⁹⁶⁶ is an apocalyptic number.

139966 is a deficient number, since it is larger than the sum of its proper divisors (74594).

139966 is a wasteful number, since it uses less digits than its factorization.

139966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538.

The product of its digits is 8748, while the sum is 34.

The square root of 139966 is about 374.1203015074. The cubic root of 139966 is about 51.9207372306.

The spelling of 139966 in words is "one hundred thirty-nine thousand, nine hundred sixty-six".