665240297 has 2 divisors, whose sum is σ = 665240298. Its totient is φ = 665240296.

The previous prime is 665240291. The next prime is 665240299. The reversal of 665240297 is 792042566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 641659561 + 23580736 = 25331^2 + 4856^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665240297 is a prime.

Together with 665240299, 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 (665240291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332620148 + 332620149.

It is an arithmetic number, because the mean of its divisors is an integer number (332620149).

Almost surely, 2^665240297 is an apocalyptic number.

It is an amenable number.

665240297 is a deficient number, since it is larger than the sum of its proper divisors (1).

665240297 is an equidigital number, since it uses as much as digits as its factorization.

665240297 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 665240297 is about 25792.2526546248. The cubic root of 665240297 is about 872.9569955377.

The spelling of 665240297 in words is "six hundred sixty-five million, two hundred forty thousand, two hundred ninety-seven".