138423305 has 8 divisors (see below), whose sum is σ = 167578632. Its totient is φ = 109758208.

The previous prime is 138423283. The next prime is 138423317. The reversal of 138423305 is 503324831.

It can be written as a sum of positive squares in 4 ways, for example, as 14167696 + 124255609 = 3764^2 + 11147^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138423305 - 2¹⁴ = 138406921 is a prime.

It is a super-2 number, since 2×138423305² = 38322022734246050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121934 + ... + 123063.

It is an arithmetic number, because the mean of its divisors is an integer number (20947329).

Almost surely, 2^138423305 is an apocalyptic number.

It is an amenable number.

138423305 is a deficient number, since it is larger than the sum of its proper divisors (29155327).

138423305 is a wasteful number, since it uses less digits than its factorization.

138423305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245115.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 138423305 is about 11765.3433864040. The cubic root of 138423305 is about 517.2927655535.

The spelling of 138423305 in words is "one hundred thirty-eight million, four hundred twenty-three thousand, three hundred five".