11659721 has 2 divisors, whose sum is σ = 11659722. Its totient is φ = 11659720.

The previous prime is 11659717. The next prime is 11659727. The reversal of 11659721 is 12795611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7639696 + 4020025 = 2764^2 + 2005^2 .

It is a cyclic number.

It is not a de Polignac number, because 11659721 - 2² = 11659717 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11659727) 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, 5829860 + 5829861.

It is an arithmetic number, because the mean of its divisors is an integer number (5829861).

Almost surely, 2^11659721 is an apocalyptic number.

It is an amenable number.

11659721 is a deficient number, since it is larger than the sum of its proper divisors (1).

11659721 is an equidigital number, since it uses as much as digits as its factorization.

11659721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 32.

The square root of 11659721 is about 3414.6333624564. The cubic root of 11659721 is about 226.7580530676.

The spelling of 11659721 in words is "eleven million, six hundred fifty-nine thousand, seven hundred twenty-one".