1216065899 has 2 divisors, whose sum is σ = 1216065900. Its totient is φ = 1216065898.

The previous prime is 1216065887. The next prime is 1216065931. The reversal of 1216065899 is 9985606121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1216065899 - 2⁴ = 1216065883 is a prime.

It is not a weakly prime, because it can be changed into another prime (1216065839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608032949 + 608032950.

It is an arithmetic number, because the mean of its divisors is an integer number (608032950).

Almost surely, 2^1216065899 is an apocalyptic number.

1216065899 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216065899 is an equidigital number, since it uses as much as digits as its factorization.

1216065899 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 233280, while the sum is 47.

The square root of 1216065899 is about 34872.1364272394. The cubic root of 1216065899 is about 1067.3799403905.

The spelling of 1216065899 in words is "one billion, two hundred sixteen million, sixty-five thousand, eight hundred ninety-nine".