138381505 has 4 divisors (see below), whose sum is σ = 166057812. Its totient is φ = 110705200.

The previous prime is 138381497. The next prime is 138381511. The reversal of 138381505 is 505183831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 34586161 + 103795344 = 5881^2 + 10188^2 .

It is not a de Polignac number, because 138381505 - 2³ = 138381497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13838146 + ... + 13838155.

It is an arithmetic number, because the mean of its divisors is an integer number (41514453).

Almost surely, 2^138381505 is an apocalyptic number.

It is an amenable number.

138381505 is a deficient number, since it is larger than the sum of its proper divisors (27676307).

138381505 is an equidigital number, since it uses as much as digits as its factorization.

138381505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27676306.

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 138381505 is about 11763.5668485371. The cubic root of 138381505 is about 517.2406909541.

The spelling of 138381505 in words is "one hundred thirty-eight million, three hundred eighty-one thousand, five hundred five".