1217204117818 has 128 divisors (see below), whose sum is σ = 2190888000000. Its totient is φ = 501771055104.

The previous prime is 1217204117807. The next prime is 1217204117897. The reversal of 1217204117818 is 8187114027121.

It is a super-2 number, since 2×1217204117818² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 352913358 + ... + 352916806.

It is an arithmetic number, because the mean of its divisors is an integer number (17116312500).

Almost surely, 2^{1217204117818} is an apocalyptic number.

1217204117818 is a deficient number, since it is larger than the sum of its proper divisors (973683882182).

1217204117818 is a wasteful number, since it uses less digits than its factorization.

1217204117818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3944.

The product of its (nonzero) digits is 50176, while the sum is 43.

The spelling of 1217204117818 in words is "one trillion, two hundred seventeen billion, two hundred four million, one hundred seventeen thousand, eight hundred eighteen".