66309855049 has 9 divisors (see below), whose sum is σ = 69988695303. Its totient is φ = 62815227552.

The previous prime is 66309855037. The next prime is 66309855097. The reversal of 66309855049 is 94055890366.

The square root of 66309855049 is 257507.

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

It can be written as a sum of positive squares in only one way, i.e., 51854121225 + 14455733824 = 227715^2 + 120232^2 .

It is not a de Polignac number, because 66309855049 - 2⁹ = 66309854537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66309855949) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4885857 + ... + 4899409.

Almost surely, 2^66309855049 is an apocalyptic number.

66309855049 is the 257507-th square number.

66309855049 is the 128754-th centered octagonal number.

It is an amenable number.

66309855049 is a deficient number, since it is larger than the sum of its proper divisors (3678840254).

66309855049 is an frugal number, since it uses more digits than its factorization.

66309855049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27144 (or 13572 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 55.

The spelling of 66309855049 in words is "sixty-six billion, three hundred nine million, eight hundred fifty-five thousand, forty-nine".