66330997 has 2 divisors, whose sum is σ = 66330998. Its totient is φ = 66330996.

The previous prime is 66330977. The next prime is 66331009. The reversal of 66330997 is 79903366.

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., 50893956 + 15437041 = 7134^2 + 3929^2 .

It is a cyclic number.

It is not a de Polignac number, because 66330997 - 2¹⁵ = 66298229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66330947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33165498 + 33165499.

It is an arithmetic number, because the mean of its divisors is an integer number (33165499).

Almost surely, 2^66330997 is an apocalyptic number.

It is an amenable number.

66330997 is a deficient number, since it is larger than the sum of its proper divisors (1).

66330997 is an equidigital number, since it uses as much as digits as its factorization.

66330997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 183708, while the sum is 43.

The square root of 66330997 is about 8144.3843843473. The cubic root of 66330997 is about 404.7984507490.

The spelling of 66330997 in words is "sixty-six million, three hundred thirty thousand, nine hundred ninety-seven".