217171835213 has 2 divisors, whose sum is σ = 217171835214. Its totient is φ = 217171835212.

The previous prime is 217171835147. The next prime is 217171835233. The reversal of 217171835213 is 312538171712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 141193323049 + 75978512164 = 375757^2 + 275642^2 .

It is a cyclic number.

It is not a de Polignac number, because 217171835213 - 2¹² = 217171831117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217171835233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108585917606 + 108585917607.

It is an arithmetic number, because the mean of its divisors is an integer number (108585917607).

Almost surely, 2^217171835213 is an apocalyptic number.

It is an amenable number.

217171835213 is a deficient number, since it is larger than the sum of its proper divisors (1).

217171835213 is an equidigital number, since it uses as much as digits as its factorization.

217171835213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 70560, while the sum is 41.

The spelling of 217171835213 in words is "two hundred seventeen billion, one hundred seventy-one million, eight hundred thirty-five thousand, two hundred thirteen".