66610069 has 2 divisors, whose sum is σ = 66610070. Its totient is φ = 66610068.

The previous prime is 66610043. The next prime is 66610079. The reversal of 66610069 is 96001666.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57380625 + 9229444 = 7575^2 + 3038^2 .

It is a cyclic number.

It is not a de Polignac number, because 66610069 - 2⁷ = 66609941 is a prime.

It is a super-2 number, since 2×66610069² = 8873802584369522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66610079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33305034 + 33305035.

It is an arithmetic number, because the mean of its divisors is an integer number (33305035).

Almost surely, 2^66610069 is an apocalyptic number.

It is an amenable number.

66610069 is a deficient number, since it is larger than the sum of its proper divisors (1).

66610069 is an equidigital number, since it uses as much as digits as its factorization.

66610069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 66610069 is about 8161.4991882619. The cubic root of 66610069 is about 405.3653544040.

The spelling of 66610069 in words is "sixty-six million, six hundred ten thousand, sixty-nine".