66385989 has 12 divisors (see below), whose sum is σ = 96033600. Its totient is φ = 44191464.

The previous prime is 66385961. The next prime is 66385999. The reversal of 66385989 is 98958366.

It is not a de Polignac number, because 66385989 - 2⁷ = 66385861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66385919) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1342 + ... + 11600.

It is an arithmetic number, because the mean of its divisors is an integer number (8002800).

Almost surely, 2^66385989 is an apocalyptic number.

It is an amenable number.

66385989 is a deficient number, since it is larger than the sum of its proper divisors (29647611).

66385989 is a wasteful number, since it uses less digits than its factorization.

66385989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10984 (or 10981 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 66385989 is about 8147.7597534537. The cubic root of 66385989 is about 404.9102864843.

The spelling of 66385989 in words is "sixty-six million, three hundred eighty-five thousand, nine hundred eighty-nine".