1939 has 4 divisors (see below), whose sum is σ = 2224. Its totient is φ = 1656.

The previous prime is 1933. The next prime is 1949. The reversal of 1939 is 9391.

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 1939 - 2³ = 1931 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a nialpdrome in base 7 and base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1931) 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 3 ways as a sum of consecutive naturals, for example, 132 + ... + 145.

It is an arithmetic number, because the mean of its divisors is an integer number (556).

1939 is a deficient number, since it is larger than the sum of its proper divisors (285).

1939 is an equidigital number, since it uses as much as digits as its factorization.

1939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284.

The product of its digits is 243, while the sum is 22.

The square root of 1939 is about 44.0340777126. The cubic root of 1939 is about 12.4697937320.

It can be divided in two parts, 193 and 9, that added together give a palindrome (202).

The spelling of 1939 in words is "one thousand, nine hundred thirty-nine".