66955563 has 12 divisors (see below), whose sum is σ = 101804040. Its totient is φ = 42287616.

The previous prime is 66955561. The next prime is 66955591. The reversal of 66955563 is 36555966.

66955563 is a `hidden beast` number, since 6 + 6 + 95 + 556 + 3 = 666.

It is not a de Polignac number, because 66955563 - 2¹ = 66955561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66955561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 195606 + ... + 195947.

It is an arithmetic number, because the mean of its divisors is an integer number (8483670).

Almost surely, 2^66955563 is an apocalyptic number.

66955563 is a deficient number, since it is larger than the sum of its proper divisors (34848477).

66955563 is a wasteful number, since it uses less digits than its factorization.

66955563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391578 (or 391575 counting only the distinct ones).

The product of its digits is 729000, while the sum is 45.

The square root of 66955563 is about 8182.6378998462. The cubic root of 66955563 is about 406.0649976422.

The spelling of 66955563 in words is "sixty-six million, nine hundred fifty-five thousand, five hundred sixty-three".