139731 has 8 divisors (see below), whose sum is σ = 190464. Its totient is φ = 91080.

The previous prime is 139729. The next prime is 139739. The reversal of 139731 is 137931.

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

It is not a de Polignac number, because 139731 - 2¹ = 139729 is a prime.

It is a super-2 number, since 2×139731² = 39049504722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (139739) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 355 + ... + 636.

It is an arithmetic number, because the mean of its divisors is an integer number (23808).

2¹³⁹⁷³¹ is an apocalyptic number.

139731 is a deficient number, since it is larger than the sum of its proper divisors (50733).

139731 is an equidigital number, since it uses as much as digits as its factorization.

139731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041.

The product of its digits is 567, while the sum is 24.

The square root of 139731 is about 373.8060994687. The cubic root of 139731 is about 51.8916630072.

The spelling of 139731 in words is "one hundred thirty-nine thousand, seven hundred thirty-one".