66989894 has 8 divisors (see below), whose sum is σ = 106395768. Its totient is φ = 31524640.

The previous prime is 66989893. The next prime is 66989917. The reversal of 66989894 is 49898966.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66989893) 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 3 ways as a sum of consecutive naturals, for example, 985112 + ... + 985179.

It is an arithmetic number, because the mean of its divisors is an integer number (13299471).

Almost surely, 2^66989894 is an apocalyptic number.

66989894 is a deficient number, since it is larger than the sum of its proper divisors (39405874).

66989894 is a wasteful number, since it uses less digits than its factorization.

66989894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1970310.

The product of its digits is 6718464, while the sum is 59.

The square root of 66989894 is about 8184.7354263898. The cubic root of 66989894 is about 406.1343881197.

The spelling of 66989894 in words is "sixty-six million, nine hundred eighty-nine thousand, eight hundred ninety-four".