1216813108373 has 4 divisors (see below), whose sum is σ = 1288390350060. Its totient is φ = 1145235866688.

The previous prime is 1216813108349. The next prime is 1216813108403. The reversal of 1216813108373 is 3738013186121.

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 783292261444 + 433520846929 = 885038^2 + 658423^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216813108373 - 2³⁸ = 941935201429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216813108073) 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, 35788620818 + ... + 35788620851.

It is an arithmetic number, because the mean of its divisors is an integer number (322097587515).

Almost surely, 2^{1216813108373} is an apocalyptic number.

It is an amenable number.

1216813108373 is a deficient number, since it is larger than the sum of its proper divisors (71577241687).

1216813108373 is an equidigital number, since it uses as much as digits as its factorization.

1216813108373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71577241686.

The product of its (nonzero) digits is 145152, while the sum is 44.

The spelling of 1216813108373 in words is "one trillion, two hundred sixteen billion, eight hundred thirteen million, one hundred eight thousand, three hundred seventy-three".