1217204117817 has 4 divisors (see below), whose sum is σ = 1622938823760. Its totient is φ = 811469411876.

The previous prime is 1217204117807. The next prime is 1217204117897. The reversal of 1217204117817 is 7187114027121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1217204117817 - 2⁸ = 1217204117561 is a prime.

It is a super-2 number, since 2×1217204117817² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1217204117807) 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 3 ways as a sum of consecutive naturals, for example, 202867352967 + ... + 202867352972.

It is an arithmetic number, because the mean of its divisors is an integer number (405734705940).

Almost surely, 2^{1217204117817} is an apocalyptic number.

It is an amenable number.

1217204117817 is a deficient number, since it is larger than the sum of its proper divisors (405734705943).

1217204117817 is an equidigital number, since it uses as much as digits as its factorization.

1217204117817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405734705942.

The product of its (nonzero) digits is 43904, while the sum is 42.

The spelling of 1217204117817 in words is "one trillion, two hundred seventeen billion, two hundred four million, one hundred seventeen thousand, eight hundred seventeen".