66006651 has 4 divisors (see below), whose sum is σ = 88008872. Its totient is φ = 44004432.

The previous prime is 66006649. The next prime is 66006667. The reversal of 66006651 is 15660066.

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

It is not a de Polignac number, because 66006651 - 2¹ = 66006649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66006601) by changing a digit.

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, 11001106 + ... + 11001111.

It is an arithmetic number, because the mean of its divisors is an integer number (22002218).

Almost surely, 2^66006651 is an apocalyptic number.

66006651 is a deficient number, since it is larger than the sum of its proper divisors (22002221).

66006651 is a wasteful number, since it uses less digits than its factorization.

66006651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22002220.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 66006651 is about 8124.4477350771. The cubic root of 66006651 is about 404.1375764989.

The spelling of 66006651 in words is "sixty-six million, six thousand, six hundred fifty-one".