66320197 has 2 divisors, whose sum is σ = 66320198. Its totient is φ = 66320196.

The previous prime is 66320183. The next prime is 66320207. The reversal of 66320197 is 79102366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58997761 + 7322436 = 7681^2 + 2706^2 .

It is a cyclic number.

It is not a de Polignac number, because 66320197 - 2¹¹ = 66318149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66320117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33160098 + 33160099.

It is an arithmetic number, because the mean of its divisors is an integer number (33160099).

Almost surely, 2^66320197 is an apocalyptic number.

It is an amenable number.

66320197 is a deficient number, since it is larger than the sum of its proper divisors (1).

66320197 is an equidigital number, since it uses as much as digits as its factorization.

66320197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 66320197 is about 8143.7213238175. The cubic root of 66320197 is about 404.7764798216.

The spelling of 66320197 in words is "sixty-six million, three hundred twenty thousand, one hundred ninety-seven".