139121439 has 16 divisors (see below), whose sum is σ = 201993600. Its totient is φ = 84835296.

The previous prime is 139121399. The next prime is 139121441. The reversal of 139121439 is 934121931.

It is a happy number.

139121439 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 139121439 - 2¹¹ = 139119391 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139121639) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40429 + ... + 43734.

It is an arithmetic number, because the mean of its divisors is an integer number (12624600).

Almost surely, 2^139121439 is an apocalyptic number.

139121439 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

139121439 is a deficient number, since it is larger than the sum of its proper divisors (62872161).

139121439 is a wasteful number, since it uses less digits than its factorization.

139121439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84214.

The product of its digits is 5832, while the sum is 33.

The square root of 139121439 is about 11794.9751589395. The cubic root of 139121439 is about 518.1609580651.

It can be divided in two parts, 13912 and 1439, that added together give a palindrome (15351).

The spelling of 139121439 in words is "one hundred thirty-nine million, one hundred twenty-one thousand, four hundred thirty-nine".