66409061 has 2 divisors, whose sum is σ = 66409062. Its totient is φ = 66409060.

The previous prime is 66409019. The next prime is 66409087. The reversal of 66409061 is 16090466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34880836 + 31528225 = 5906^2 + 5615^2 .

It is a cyclic number.

It is not a de Polignac number, because 66409061 - 2¹⁰ = 66408037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66403061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33204530 + 33204531.

It is an arithmetic number, because the mean of its divisors is an integer number (33204531).

Almost surely, 2^66409061 is an apocalyptic number.

It is an amenable number.

66409061 is a deficient number, since it is larger than the sum of its proper divisors (1).

66409061 is an equidigital number, since it uses as much as digits as its factorization.

66409061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 66409061 is about 8149.1754797648. The cubic root of 66409061 is about 404.9571889920.

The spelling of 66409061 in words is "sixty-six million, four hundred nine thousand, sixty-one".