7128139 has 2 divisors, whose sum is σ = 7128140. Its totient is φ = 7128138.

The previous prime is 7128101. The next prime is 7128167. The reversal of 7128139 is 9318217.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7128139 - 2¹⁵ = 7095371 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7128139.

It is not a weakly prime, because it can be changed into another prime (7128739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3564069 + 3564070.

It is an arithmetic number, because the mean of its divisors is an integer number (3564070).

Almost surely, 2^7128139 is an apocalyptic number.

7128139 is a deficient number, since it is larger than the sum of its proper divisors (1).

7128139 is an equidigital number, since it uses as much as digits as its factorization.

7128139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3024, while the sum is 31.

The square root of 7128139 is about 2669.8574868333. The cubic root of 7128139 is about 192.4533107660.

The spelling of 7128139 in words is "seven million, one hundred twenty-eight thousand, one hundred thirty-nine".