138811308857 has 4 divisors (see below), whose sum is σ = 149489101860. Its totient is φ = 128133515856.

The previous prime is 138811308829. The next prime is 138811308869. The reversal of 138811308857 is 758803118831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 758803118831 = 107 ⋅7091617933.

It can be written as a sum of positive squares in 2 ways, for example, as 95740117561 + 43071191296 = 309419^2 + 207536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138811308857 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138811308799 and 138811308808.

It is not an unprimeable number, because it can be changed into a prime (138811301857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5338896482 + ... + 5338896507.

It is an arithmetic number, because the mean of its divisors is an integer number (37372275465).

Almost surely, 2^138811308857 is an apocalyptic number.

It is an amenable number.

138811308857 is a deficient number, since it is larger than the sum of its proper divisors (10677793003).

138811308857 is a wasteful number, since it uses less digits than its factorization.

138811308857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10677793002.

The product of its (nonzero) digits is 1290240, while the sum is 53.

The spelling of 138811308857 in words is "one hundred thirty-eight billion, eight hundred eleven million, three hundred eight thousand, eight hundred fifty-seven".