138137506 has 16 divisors (see below), whose sum is σ = 225449784. Its totient is φ = 63097344.

The previous prime is 138137501. The next prime is 138137509. The reversal of 138137506 is 605731831.

It can be written as a sum of positive squares in 4 ways, for example, as 124880625 + 13256881 = 11175^2 + 3641^2 .

It is not an unprimeable number, because it can be changed into a prime (138137501) 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, 24865 + ... + 29908.

Almost surely, 2^138137506 is an apocalyptic number.

138137506 is a deficient number, since it is larger than the sum of its proper divisors (87312278).

138137506 is a wasteful number, since it uses less digits than its factorization.

138137506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54885.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 138137506 is about 11753.1913112992. The cubic root of 138137506 is about 516.9365066121.

The spelling of 138137506 in words is "one hundred thirty-eight million, one hundred thirty-seven thousand, five hundred six".