216671516993 has 2 divisors, whose sum is σ = 216671516994. Its totient is φ = 216671516992.

The previous prime is 216671516927. The next prime is 216671517053. The reversal of 216671516993 is 399615176612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145399603969 + 71271913024 = 381313^2 + 266968^2 .

It is a cyclic number.

It is not a de Polignac number, because 216671516993 - 2²² = 216667322689 is a prime.

It is not a weakly prime, because it can be changed into another prime (216671516693) 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, 108335758496 + 108335758497.

It is an arithmetic number, because the mean of its divisors is an integer number (108335758497).

Almost surely, 2^216671516993 is an apocalyptic number.

It is an amenable number.

216671516993 is a deficient number, since it is larger than the sum of its proper divisors (1).

216671516993 is an equidigital number, since it uses as much as digits as its factorization.

216671516993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3674160, while the sum is 56.

The spelling of 216671516993 in words is "two hundred sixteen billion, six hundred seventy-one million, five hundred sixteen thousand, nine hundred ninety-three".