65606991449 has 2 divisors, whose sum is σ = 65606991450. Its totient is φ = 65606991448.

The previous prime is 65606991433. The next prime is 65606991451. The reversal of 65606991449 is 94419960656.

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., 58446447049 + 7160544400 = 241757^2 + 84620^2 .

It is a cyclic number.

It is not a de Polignac number, because 65606991449 - 2⁴ = 65606991433 is a prime.

It is a Sophie Germain prime.

Together with 65606991451, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (65606291449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32803495724 + 32803495725.

It is an arithmetic number, because the mean of its divisors is an integer number (32803495725).

Almost surely, 2^65606991449 is an apocalyptic number.

It is an amenable number.

65606991449 is a deficient number, since it is larger than the sum of its proper divisors (1).

65606991449 is an equidigital number, since it uses as much as digits as its factorization.

65606991449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12597120, while the sum is 59.

The spelling of 65606991449 in words is "sixty-five billion, six hundred six million, nine hundred ninety-one thousand, four hundred forty-nine".