11721779 has 2 divisors, whose sum is σ = 11721780. Its totient is φ = 11721778.

The previous prime is 11721769. The next prime is 11721781. The reversal of 11721779 is 97712711.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11721779 - 2⁴ = 11721763 is a prime.

It is a Sophie Germain prime.

Together with 11721781, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11721769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5860889 + 5860890.

It is an arithmetic number, because the mean of its divisors is an integer number (5860890).

Almost surely, 2^11721779 is an apocalyptic number.

11721779 is a deficient number, since it is larger than the sum of its proper divisors (1).

11721779 is an equidigital number, since it uses as much as digits as its factorization.

11721779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6174, while the sum is 35.

The square root of 11721779 is about 3423.7083695899. The cubic root of 11721779 is about 227.1596424031.

The spelling of 11721779 in words is "eleven million, seven hundred twenty-one thousand, seven hundred seventy-nine".