1216650605217 has 4 divisors (see below), whose sum is σ = 1622200806960. Its totient is φ = 811100403476.

The previous prime is 1216650605189. The next prime is 1216650605249. The reversal of 1216650605217 is 7125060566121.

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 1216650605217 - 2¹⁶ = 1216650539681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1216650615217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202775100867 + ... + 202775100872.

It is an arithmetic number, because the mean of its divisors is an integer number (405550201740).

Almost surely, 2^{1216650605217} is an apocalyptic number.

It is an amenable number.

1216650605217 is a deficient number, since it is larger than the sum of its proper divisors (405550201743).

1216650605217 is an equidigital number, since it uses as much as digits as its factorization.

1216650605217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405550201742.

The product of its (nonzero) digits is 151200, while the sum is 42.

The spelling of 1216650605217 in words is "one trillion, two hundred sixteen billion, six hundred fifty million, six hundred five thousand, two hundred seventeen".