138951539 has 4 divisors (see below), whose sum is σ = 142707024. Its totient is φ = 135196056.

The previous prime is 138951521. The next prime is 138951563. The reversal of 138951539 is 935159831.

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 138951539 - 2¹⁶ = 138886003 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138951539.

It is not an unprimeable number, because it can be changed into a prime (138951509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1877687 + ... + 1877760.

It is an arithmetic number, because the mean of its divisors is an integer number (35676756).

Almost surely, 2^138951539 is an apocalyptic number.

138951539 is a deficient number, since it is larger than the sum of its proper divisors (3755485).

138951539 is an equidigital number, since it uses as much as digits as its factorization.

138951539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3755484.

The product of its digits is 145800, while the sum is 44.

The square root of 138951539 is about 11787.7707392026. The cubic root of 138951539 is about 517.9499400051.

The spelling of 138951539 in words is "one hundred thirty-eight million, nine hundred fifty-one thousand, five hundred thirty-nine".