6561199 has 2 divisors, whose sum is σ = 6561200. Its totient is φ = 6561198.

The previous prime is 6561197. The next prime is 6561209. The reversal of 6561199 is 9911656.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6561199 - 2¹ = 6561197 is a prime.

Together with 6561197, it forms a pair of twin primes.

6561199 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6561193) 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, 3280599 + 3280600.

It is an arithmetic number, because the mean of its divisors is an integer number (3280600).

Almost surely, 2^6561199 is an apocalyptic number.

6561199 is a deficient number, since it is larger than the sum of its proper divisors (1).

6561199 is an equidigital number, since it uses as much as digits as its factorization.

6561199 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14580, while the sum is 37.

The square root of 6561199 is about 2561.4837497045. The cubic root of 6561199 is about 187.2094367701.

The spelling of 6561199 in words is "six million, five hundred sixty-one thousand, one hundred ninety-nine".