6855139 has 2 divisors, whose sum is σ = 6855140. Its totient is φ = 6855138.

The previous prime is 6855137. The next prime is 6855157. The reversal of 6855139 is 9315586.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6855139 - 2¹ = 6855137 is a prime.

Together with 6855137, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 6855098 and 6855107.

It is not a weakly prime, because it can be changed into another prime (6855133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3427569 + 3427570.

It is an arithmetic number, because the mean of its divisors is an integer number (3427570).

Almost surely, 2^6855139 is an apocalyptic number.

6855139 is a deficient number, since it is larger than the sum of its proper divisors (1).

6855139 is an equidigital number, since it uses as much as digits as its factorization.

6855139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 37.

The square root of 6855139 is about 2618.2320370815. The cubic root of 6855139 is about 189.9643423389.

The spelling of 6855139 in words is "six million, eight hundred fifty-five thousand, one hundred thirty-nine".