138944799009 has 45 divisors (see below), whose sum is σ = 210512227233. Its totient is φ = 91330449048.

The previous prime is 138944798977. The next prime is 138944799023. The reversal of 138944799009 is 900997449831.

The square root of 138944799009 is 372753.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 138944799009 - 2⁵ = 138944798977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138944799079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 278446242 + ... + 278446740.

Almost surely, 2^138944799009 is an apocalyptic number.

138944799009 is the 372753-rd square number.

138944799009 is the 186377-th centered octagonal number.

It is an amenable number.

138944799009 is a deficient number, since it is larger than the sum of its proper divisors (71567428224).

138944799009 is an frugal number, since it uses more digits than its factorization.

138944799009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1176 (or 585 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 138944799009 in words is "one hundred thirty-eight billion, nine hundred forty-four million, seven hundred ninety-nine thousand, nine".