66469649849 has 2 divisors, whose sum is σ = 66469649850. Its totient is φ = 66469649848.

The previous prime is 66469649801. The next prime is 66469649863. The reversal of 66469649849 is 94894696466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43219499449 + 23250150400 = 207893^2 + 152480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66469649849 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (66469649149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33234824924 + 33234824925.

It is an arithmetic number, because the mean of its divisors is an integer number (33234824925).

Almost surely, 2^66469649849 is an apocalyptic number.

It is an amenable number.

66469649849 is a deficient number, since it is larger than the sum of its proper divisors (1).

66469649849 is an equidigital number, since it uses as much as digits as its factorization.

66469649849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483729408, while the sum is 71.

The spelling of 66469649849 in words is "sixty-six billion, four hundred sixty-nine million, six hundred forty-nine thousand, eight hundred forty-nine".