217638328867 has 2 divisors, whose sum is σ = 217638328868. Its totient is φ = 217638328866.

The previous prime is 217638328823. The next prime is 217638328879. The reversal of 217638328867 is 768823836712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 217638328867 - 2³⁵ = 183278590499 is a prime.

It is not a weakly prime, because it can be changed into another prime (217638328807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108819164433 + 108819164434.

It is an arithmetic number, because the mean of its divisors is an integer number (108819164434).

Almost surely, 2^217638328867 is an apocalyptic number.

217638328867 is a deficient number, since it is larger than the sum of its proper divisors (1).

217638328867 is an equidigital number, since it uses as much as digits as its factorization.

217638328867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32514048, while the sum is 61.

The spelling of 217638328867 in words is "two hundred seventeen billion, six hundred thirty-eight million, three hundred twenty-eight thousand, eight hundred sixty-seven".