7066721 has 2 divisors, whose sum is σ = 7066722. Its totient is φ = 7066720.

The previous prime is 7066699. The next prime is 7066723. The reversal of 7066721 is 1276607.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6964321 + 102400 = 2639^2 + 320^2 .

It is a cyclic number.

It is not a de Polignac number, because 7066721 - 2²² = 2872417 is a prime.

Together with 7066723, 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 (7066723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3533360 + 3533361.

It is an arithmetic number, because the mean of its divisors is an integer number (3533361).

Almost surely, 2^7066721 is an apocalyptic number.

It is an amenable number.

7066721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7066721 is an equidigital number, since it uses as much as digits as its factorization.

7066721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528, while the sum is 29.

The square root of 7066721 is about 2658.3304911166. The cubic root of 7066721 is about 191.8989720957.

The spelling of 7066721 in words is "seven million, sixty-six thousand, seven hundred twenty-one".