217671478553 has 2 divisors, whose sum is σ = 217671478554. Its totient is φ = 217671478552.

The previous prime is 217671478513. The next prime is 217671478589. The reversal of 217671478553 is 355874176712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217554146329 + 117332224 = 466427^2 + 10832^2 .

It is a cyclic number.

It is not a de Polignac number, because 217671478553 - 2²⁴ = 217654701337 is a prime.

It is not a weakly prime, because it can be changed into another prime (217671478513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108835739276 + 108835739277.

It is an arithmetic number, because the mean of its divisors is an integer number (108835739277).

Almost surely, 2^217671478553 is an apocalyptic number.

It is an amenable number.

217671478553 is a deficient number, since it is larger than the sum of its proper divisors (1).

217671478553 is an equidigital number, since it uses as much as digits as its factorization.

217671478553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9878400, while the sum is 56.

The spelling of 217671478553 in words is "two hundred seventeen billion, six hundred seventy-one million, four hundred seventy-eight thousand, five hundred fifty-three".