66096810649 has 3 divisors (see below), whose sum is σ = 66097067743. Its totient is φ = 66096553556.

The previous prime is 66096810599. The next prime is 66096810683. The reversal of 66096810649 is 94601869066.

The square root of 66096810649 is 257093.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 8529446025 + 57567364624 = 92355^2 + 239932^2 .

It is not a de Polignac number, because 66096810649 - 2⁹ = 66096810137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66096810649.

It is not an unprimeable number, because it can be changed into a prime (66096820649) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 128547 + ... + 385639.

Almost surely, 2^66096810649 is an apocalyptic number.

66096810649 is the 257093-rd square number.

66096810649 is the 128547-th centered octagonal number.

It is an amenable number.

66096810649 is a deficient number, since it is larger than the sum of its proper divisors (257094).

66096810649 is an frugal number, since it uses more digits than its factorization.

66096810649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514186 (or 257093 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 55.

The spelling of 66096810649 in words is "sixty-six billion, ninety-six million, eight hundred ten thousand, six hundred forty-nine".