133939 has 4 divisors (see below), whose sum is σ = 144256. Its totient is φ = 123624.

The previous prime is 133919. The next prime is 133949. The reversal of 133939 is 939331.

133939 = T₁₃₇ + T₁₃₈ + ... + T₁₄₉.

It is a happy number.

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 133939 - 2⁷ = 133811 is a prime.

It is a Duffinian number.

133939 is a modest number, since divided by 3939 gives 13 as remainder.

133939 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (133919) 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, 5139 + ... + 5164.

It is an arithmetic number, because the mean of its divisors is an integer number (36064).

2¹³³⁹³⁹ is an apocalyptic number.

133939 is a deficient number, since it is larger than the sum of its proper divisors (10317).

133939 is a wasteful number, since it uses less digits than its factorization.

133939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10316.

The product of its digits is 2187, while the sum is 28.

The square root of 133939 is about 365.9767752194. The cubic root of 133939 is about 51.1645333396.

It can be divided in two parts, 1339 and 39, that added together give a triangular number (1378 = T₅₂).

The spelling of 133939 in words is "one hundred thirty-three thousand, nine hundred thirty-nine".