6438243139 has 4 divisors (see below), whose sum is σ = 6495218856. Its totient is φ = 6381267424.

The previous prime is 6438243137. The next prime is 6438243143. The reversal of 6438243139 is 9313428346.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9313428346 = 2 ⋅4656714173.

It is a cyclic number.

It is not a de Polignac number, because 6438243139 - 2¹ = 6438243137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6438243095 and 6438243104.

It is not an unprimeable number, because it can be changed into a prime (6438243137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28487689 + ... + 28487914.

It is an arithmetic number, because the mean of its divisors is an integer number (1623804714).

Almost surely, 2^6438243139 is an apocalyptic number.

6438243139 is a deficient number, since it is larger than the sum of its proper divisors (56975717).

6438243139 is a wasteful number, since it uses less digits than its factorization.

6438243139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56975716.

The product of its digits is 373248, while the sum is 43.

The square root of 6438243139 is about 80238.6636167378. The cubic root of 6438243139 is about 1860.3262944534.

The spelling of 6438243139 in words is "six billion, four hundred thirty-eight million, two hundred forty-three thousand, one hundred thirty-nine".