66430777555 has 16 divisors (see below), whose sum is σ = 79827223680. Its totient is φ = 53071157248.

The previous prime is 66430777507. The next prime is 66430777631. The reversal of 66430777555 is 55577703466.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66430777555 - 2⁹ = 66430777043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66430777496 and 66430777505.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16284006 + ... + 16288084.

It is an arithmetic number, because the mean of its divisors is an integer number (4989201480).

Almost surely, 2^66430777555 is an apocalyptic number.

66430777555 is a deficient number, since it is larger than the sum of its proper divisors (13396446125).

66430777555 is a wasteful number, since it uses less digits than its factorization.

66430777555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7790.

The product of its (nonzero) digits is 18522000, while the sum is 55.

The spelling of 66430777555 in words is "sixty-six billion, four hundred thirty million, seven hundred seventy-seven thousand, five hundred fifty-five".