216661699 has 2 divisors, whose sum is σ = 216661700. Its totient is φ = 216661698.

The previous prime is 216661667. The next prime is 216661703. The reversal of 216661699 is 996166612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 216661699 - 2⁵ = 216661667 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (216661499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108330849 + 108330850.

It is an arithmetic number, because the mean of its divisors is an integer number (108330850).

Almost surely, 2^216661699 is an apocalyptic number.

216661699 is a deficient number, since it is larger than the sum of its proper divisors (1).

216661699 is an equidigital number, since it uses as much as digits as its factorization.

216661699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 46.

The square root of 216661699 is about 14719.4326996661. The cubic root of 216661699 is about 600.6120596852.

The spelling of 216661699 in words is "two hundred sixteen million, six hundred sixty-one thousand, six hundred ninety-nine".