6399427 has 2 divisors, whose sum is σ = 6399428. Its totient is φ = 6399426.

The previous prime is 6399397. The next prime is 6399433. The reversal of 6399427 is 7249936.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6399427 is a prime.

It is an Ulam number.

6399427 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6399427.

It is not a weakly prime, because it can be changed into another prime (6399457) 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, 3199713 + 3199714.

It is an arithmetic number, because the mean of its divisors is an integer number (3199714).

Almost surely, 2^6399427 is an apocalyptic number.

6399427 is a deficient number, since it is larger than the sum of its proper divisors (1).

6399427 is an equidigital number, since it uses as much as digits as its factorization.

6399427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 40.

The square root of 6399427 is about 2529.7088765311. The cubic root of 6399427 is about 185.6580122825.

The spelling of 6399427 in words is "six million, three hundred ninety-nine thousand, four hundred twenty-seven".