6420899 has 2 divisors, whose sum is σ = 6420900. Its totient is φ = 6420898.

The previous prime is 6420893. The next prime is 6420901. The reversal of 6420899 is 9980246.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6420899 is a prime.

Together with 6420901, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (6420893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210449 + 3210450.

It is an arithmetic number, because the mean of its divisors is an integer number (3210450).

Almost surely, 2^6420899 is an apocalyptic number.

6420899 is a deficient number, since it is larger than the sum of its proper divisors (1).

6420899 is an equidigital number, since it uses as much as digits as its factorization.

6420899 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 6420899 is about 2533.9492891532. The cubic root of 6420899 is about 185.8654266106.

The spelling of 6420899 in words is "six million, four hundred twenty thousand, eight hundred ninety-nine".