12551216917 has 4 divisors (see below), whose sum is σ = 12614928876. Its totient is φ = 12487504960.

The previous prime is 12551216903. The next prime is 12551216927. The reversal of 12551216917 is 71961215521.

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 9575405316 + 2975811601 = 97854^2 + 54551^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12551216917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12551216917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12551216927) 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, 31855684 + ... + 31856077.

It is an arithmetic number, because the mean of its divisors is an integer number (3153732219).

Almost surely, 2^12551216917 is an apocalyptic number.

It is an amenable number.

12551216917 is a deficient number, since it is larger than the sum of its proper divisors (63711959).

12551216917 is an equidigital number, since it uses as much as digits as its factorization.

12551216917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63711958.

The product of its digits is 37800, while the sum is 40.

The spelling of 12551216917 in words is "twelve billion, five hundred fifty-one million, two hundred sixteen thousand, nine hundred seventeen".