138492505 has 4 divisors (see below), whose sum is σ = 166191012. Its totient is φ = 110794000.

The previous prime is 138492493. The next prime is 138492527. The reversal of 138492505 is 505294831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 505294831 = 73 ⋅6921847.

It can be written as a sum of positive squares in 2 ways, for example, as 18896409 + 119596096 = 4347^2 + 10936^2 .

It is not a de Polignac number, because 138492505 - 2⁷ = 138492377 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 13849246 + ... + 13849255.

It is an arithmetic number, because the mean of its divisors is an integer number (41547753).

Almost surely, 2^138492505 is an apocalyptic number.

It is an amenable number.

138492505 is a deficient number, since it is larger than the sum of its proper divisors (27698507).

138492505 is an equidigital number, since it uses as much as digits as its factorization.

138492505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27698506.

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 138492505 is about 11768.2838595948. The cubic root of 138492505 is about 517.3789521388.

The spelling of 138492505 in words is "one hundred thirty-eight million, four hundred ninety-two thousand, five hundred five".