138823647 has 4 divisors (see below), whose sum is σ = 185098200. Its totient is φ = 92549096.

The previous prime is 138823631. The next prime is 138823679. The reversal of 138823647 is 746328831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 746328831 = 3 ⋅248776277.

It is a cyclic number.

It is not a de Polignac number, because 138823647 - 2⁴ = 138823631 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138823599 and 138823608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138823687) 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, 23137272 + ... + 23137277.

It is an arithmetic number, because the mean of its divisors is an integer number (46274550).

Almost surely, 2^138823647 is an apocalyptic number.

138823647 is a deficient number, since it is larger than the sum of its proper divisors (46274553).

138823647 is an equidigital number, since it uses as much as digits as its factorization.

138823647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46274552.

The product of its digits is 193536, while the sum is 42.

The square root of 138823647 is about 11782.3447157177. The cubic root of 138823647 is about 517.7909829383.

It can be divided in two parts, 13 and 8823647, that multiplied together give a palindrome (114707411).

The spelling of 138823647 in words is "one hundred thirty-eight million, eight hundred twenty-three thousand, six hundred forty-seven".