217306253115561 has 8 divisors (see below), whose sum is σ = 290014240600000. Its totient is φ = 144734550520752.

The previous prime is 217306253115527. The next prime is 217306253115563. The reversal of 217306253115561 is 165511352603712.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 217306253115561 - 2⁷ = 217306253115433 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 217306253115561.

It is not an unprimeable number, because it can be changed into a prime (217306253115563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34071218686 + ... + 34071225063.

It is an arithmetic number, because the mean of its divisors is an integer number (36251780075000).

Almost surely, 2^{217306253115561} is an apocalyptic number.

It is an amenable number.

217306253115561 is a deficient number, since it is larger than the sum of its proper divisors (72707987484439).

217306253115561 is a wasteful number, since it uses less digits than its factorization.

217306253115561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68142444815.

The product of its (nonzero) digits is 1134000, while the sum is 48.

The spelling of 217306253115561 in words is "two hundred seventeen trillion, three hundred six billion, two hundred fifty-three million, one hundred fifteen thousand, five hundred sixty-one".