12347765521 has 16 divisors (see below), whose sum is σ = 15208850944. Its totient is φ = 9762202944.

The previous prime is 12347765509. The next prime is 12347765537. The reversal of 12347765521 is 12556774321.

It is a happy number.

It is not a de Polignac number, because 12347765521 - 2⁹ = 12347765009 is a prime.

It is the 111121-st Hogben number.

It is not an unprimeable number, because it can be changed into a prime (12347765501) by changing a digit.

It is a nontrivial repunit in base 111120.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69631 + ... + 171883.

It is an arithmetic number, because the mean of its divisors is an integer number (950553184).

Almost surely, 2^12347765521 is an apocalyptic number.

It is an amenable number.

12347765521 is a deficient number, since it is larger than the sum of its proper divisors (2861085423).

12347765521 is a wasteful number, since it uses less digits than its factorization.

12347765521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103600.

The product of its digits is 352800, while the sum is 43.

The spelling of 12347765521 in words is "twelve billion, three hundred forty-seven million, seven hundred sixty-five thousand, five hundred twenty-one".