11807712821 has 2 divisors, whose sum is σ = 11807712822. Its totient is φ = 11807712820.

The previous prime is 11807712817. The next prime is 11807712827. The reversal of 11807712821 is 12821770811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6578832100 + 5228880721 = 81110^2 + 72311^2 .

It is a cyclic number.

It is not a de Polignac number, because 11807712821 - 2² = 11807712817 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11807712827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5903856410 + 5903856411.

It is an arithmetic number, because the mean of its divisors is an integer number (5903856411).

Almost surely, 2^11807712821 is an apocalyptic number.

It is an amenable number.

11807712821 is a deficient number, since it is larger than the sum of its proper divisors (1).

11807712821 is an equidigital number, since it uses as much as digits as its factorization.

11807712821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12544, while the sum is 38.

The spelling of 11807712821 in words is "eleven billion, eight hundred seven million, seven hundred twelve thousand, eight hundred twenty-one".