11647306721 has 2 divisors, whose sum is σ = 11647306722. Its totient is φ = 11647306720.

The previous prime is 11647306703. The next prime is 11647306729. The reversal of 11647306721 is 12760374611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11586154321 + 61152400 = 107639^2 + 7820^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11647306721 is a prime.

It is not a weakly prime, because it can be changed into another prime (11647306729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5823653360 + 5823653361.

It is an arithmetic number, because the mean of its divisors is an integer number (5823653361).

Almost surely, 2^11647306721 is an apocalyptic number.

It is an amenable number.

11647306721 is a deficient number, since it is larger than the sum of its proper divisors (1).

11647306721 is an equidigital number, since it uses as much as digits as its factorization.

11647306721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 38.

The spelling of 11647306721 in words is "eleven billion, six hundred forty-seven million, three hundred six thousand, seven hundred twenty-one".