11786646721 has 2 divisors, whose sum is σ = 11786646722. Its totient is φ = 11786646720.

The previous prime is 11786646719. The next prime is 11786646757. The reversal of 11786646721 is 12764668711.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6705808321 + 5080838400 = 81889^2 + 71280^2 .

It is a cyclic number.

It is not a de Polignac number, because 11786646721 - 2¹ = 11786646719 is a prime.

Together with 11786646719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (11786646821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5893323360 + 5893323361.

It is an arithmetic number, because the mean of its divisors is an integer number (5893323361).

Almost surely, 2^11786646721 is an apocalyptic number.

It is an amenable number.

11786646721 is a deficient number, since it is larger than the sum of its proper divisors (1).

11786646721 is an equidigital number, since it uses as much as digits as its factorization.

11786646721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 677376, while the sum is 49.

The spelling of 11786646721 in words is "eleven billion, seven hundred eighty-six million, six hundred forty-six thousand, seven hundred twenty-one".