139236905 has 16 divisors (see below), whose sum is σ = 169355664. Its totient is φ = 109885440.

The previous prime is 139236901. The next prime is 139236907. The reversal of 139236905 is 509632931.

It can be written as a sum of positive squares in 8 ways, for example, as 1948816 + 137288089 = 1396^2 + 11717^2 .

It is not a de Polignac number, because 139236905 - 2² = 139236901 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139236901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158327 + ... + 159203.

It is an arithmetic number, because the mean of its divisors is an integer number (10584729).

Almost surely, 2^139236905 is an apocalyptic number.

It is an amenable number.

139236905 is a deficient number, since it is larger than the sum of its proper divisors (30118759).

139236905 is a wasteful number, since it uses less digits than its factorization.

139236905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1276.

The product of its (nonzero) digits is 43740, while the sum is 38.

The square root of 139236905 is about 11799.8688552034. The cubic root of 139236905 is about 518.3042703371.

The spelling of 139236905 in words is "one hundred thirty-nine million, two hundred thirty-six thousand, nine hundred five".