66499895549 has 2 divisors, whose sum is σ = 66499895550. Its totient is φ = 66499895548.

The previous prime is 66499895521. The next prime is 66499895569. The reversal of 66499895549 is 94559899466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35702102500 + 30797793049 = 188950^2 + 175493^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66499895549 is a prime.

It is a super-2 number, since 2×66499895549² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66499895569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33249947774 + 33249947775.

It is an arithmetic number, because the mean of its divisors is an integer number (33249947775).

Almost surely, 2^66499895549 is an apocalyptic number.

It is an amenable number.

66499895549 is a deficient number, since it is larger than the sum of its proper divisors (1).

66499895549 is an equidigital number, since it uses as much as digits as its factorization.

66499895549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 755827200, while the sum is 74.

The spelling of 66499895549 in words is "sixty-six billion, four hundred ninety-nine million, eight hundred ninety-five thousand, five hundred forty-nine".