139523 has 6 divisors (see below), whose sum is σ = 144732. Its totient is φ = 134480.

The previous prime is 139511. The next prime is 139537. The reversal of 139523 is 325931.

It is a happy number.

139523 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It is not a de Polignac number, because 139523 - 2⁶ = 139459 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12 and base 14.

It is not an unprimeable number, because it can be changed into a prime (139123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1640 + ... + 1722.

It is an arithmetic number, because the mean of its divisors is an integer number (24122).

2¹³⁹⁵²³ is an apocalyptic number.

139523 is a deficient number, since it is larger than the sum of its proper divisors (5209).

139523 is an frugal number, since it uses more digits than its factorization.

139523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 124 counting only the distinct ones).

The product of its digits is 810, while the sum is 23.

The square root of 139523 is about 373.5277767449. The cubic root of 139523 is about 51.8659020189.

The spelling of 139523 in words is "one hundred thirty-nine thousand, five hundred twenty-three".