139381 has 4 divisors (see below), whose sum is σ = 152064. Its totient is φ = 126700.

The previous prime is 139369. The next prime is 139387. The reversal of 139381 is 183931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 139381 - 2⁹ = 138869 is a prime.

It is a super-2 number, since 2×139381² = 38854126322, which contains 22 as substring.

139381 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139387) 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, 6325 + ... + 6346.

It is an arithmetic number, because the mean of its divisors is an integer number (38016).

2¹³⁹³⁸¹ is an apocalyptic number.

139381 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

139381 is a deficient number, since it is larger than the sum of its proper divisors (12683).

139381 is a wasteful number, since it uses less digits than its factorization.

139381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12682.

The product of its digits is 648, while the sum is 25.

The square root of 139381 is about 373.3376487846. The cubic root of 139381 is about 51.8483004811.

The spelling of 139381 in words is "one hundred thirty-nine thousand, three hundred eighty-one".