217331531447293 has 2 divisors, whose sum is σ = 217331531447294. Its totient is φ = 217331531447292.

The previous prime is 217331531447291. The next prime is 217331531447351. The reversal of 217331531447293 is 392744135133712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 217240567680889 + 90963766404 = 14739083^2 + 301602^2 .

It is a cyclic number.

It is not a de Polignac number, because 217331531447293 - 2¹ = 217331531447291 is a prime.

It is a super-2 number, since 2×217331531447293² (a number of 29 digits) contains 22 as substring.

Together with 217331531447291, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (217331531447291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108665765723646 + 108665765723647.

It is an arithmetic number, because the mean of its divisors is an integer number (108665765723647).

Almost surely, 2^{217331531447293} is an apocalyptic number.

It is an amenable number.

217331531447293 is a deficient number, since it is larger than the sum of its proper divisors (1).

217331531447293 is an equidigital number, since it uses as much as digits as its factorization.

217331531447293 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11430720, while the sum is 55.

The spelling of 217331531447293 in words is "two hundred seventeen trillion, three hundred thirty-one billion, five hundred thirty-one million, four hundred forty-seven thousand, two hundred ninety-three".