66980855 has 4 divisors (see below), whose sum is σ = 80377032. Its totient is φ = 53584680.

The previous prime is 66980819. The next prime is 66980869. The reversal of 66980855 is 55808966.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66980855 - 2⁶ = 66980791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6698081 + ... + 6698090.

It is an arithmetic number, because the mean of its divisors is an integer number (20094258).

Almost surely, 2^66980855 is an apocalyptic number.

66980855 is a deficient number, since it is larger than the sum of its proper divisors (13396177).

66980855 is a wasteful number, since it uses less digits than its factorization.

66980855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13396176.

The product of its (nonzero) digits is 518400, while the sum is 47.

The square root of 66980855 is about 8184.1832213117. The cubic root of 66980855 is about 406.1161206187.

The spelling of 66980855 in words is "sixty-six million, nine hundred eighty thousand, eight hundred fifty-five".