217606811393 has 2 divisors, whose sum is σ = 217606811394. Its totient is φ = 217606811392.

The previous prime is 217606811351. The next prime is 217606811423. The reversal of 217606811393 is 393118606712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193967133889 + 23639677504 = 440417^2 + 153752^2 .

It is a cyclic number.

It is not a de Polignac number, because 217606811393 - 2¹⁸ = 217606549249 is a prime.

It is not a weakly prime, because it can be changed into another prime (217606816393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108803405696 + 108803405697.

It is an arithmetic number, because the mean of its divisors is an integer number (108803405697).

Almost surely, 2^217606811393 is an apocalyptic number.

It is an amenable number.

217606811393 is a deficient number, since it is larger than the sum of its proper divisors (1).

217606811393 is an equidigital number, since it uses as much as digits as its factorization.

217606811393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 47.

The spelling of 217606811393 in words is "two hundred seventeen billion, six hundred six million, eight hundred eleven thousand, three hundred ninety-three".