1217520216643 has 4 divisors (see below), whose sum is σ = 1217570268520. Its totient is φ = 1217470164768.

The previous prime is 1217520216629. The next prime is 1217520216683. The reversal of 1217520216643 is 3466120257121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1217520216643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1217520216596 and 1217520216605.

It is not an unprimeable number, because it can be changed into a prime (1217520216683) 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, 24989433 + ... + 25038106.

It is an arithmetic number, because the mean of its divisors is an integer number (304392567130).

Almost surely, 2^{1217520216643} is an apocalyptic number.

1217520216643 is a deficient number, since it is larger than the sum of its proper divisors (50051877).

1217520216643 is an equidigital number, since it uses as much as digits as its factorization.

1217520216643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50051876.

The product of its (nonzero) digits is 120960, while the sum is 40.

The spelling of 1217520216643 in words is "one trillion, two hundred seventeen billion, five hundred twenty million, two hundred sixteen thousand, six hundred forty-three".