1217721371417 has 4 divisors (see below), whose sum is σ = 1217928437556. Its totient is φ = 1217514305280.

The previous prime is 1217721371411. The next prime is 1217721371431. The reversal of 1217721371417 is 7141731277121.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1150007443456 + 67713927961 = 1072384^2 + 260219^2 .

It is a cyclic number.

It is not a de Polignac number, because 1217721371417 - 2⁶ = 1217721371353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1217721371411) 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, 103524248 + ... + 103536009.

It is an arithmetic number, because the mean of its divisors is an integer number (304482109389).

Almost surely, 2^{1217721371417} is an apocalyptic number.

It is an amenable number.

1217721371417 is a deficient number, since it is larger than the sum of its proper divisors (207066139).

1217721371417 is an equidigital number, since it uses as much as digits as its factorization.

1217721371417 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207066138.

The product of its digits is 115248, while the sum is 44.

The spelling of 1217721371417 in words is "one trillion, two hundred seventeen billion, seven hundred twenty-one million, three hundred seventy-one thousand, four hundred seventeen".