66639702 has 32 divisors (see below), whose sum is σ = 136691712. Its totient is φ = 21648704.

The previous prime is 66639667. The next prime is 66639751. The reversal of 66639702 is 20793666.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 107698 + ... + 108314.

It is an arithmetic number, because the mean of its divisors is an integer number (4271616).

Almost surely, 2^66639702 is an apocalyptic number.

66639702 is an abundant number, since it is smaller than the sum of its proper divisors (70052010).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66639702 is a wasteful number, since it uses less digits than its factorization.

66639702 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1052.

The product of its (nonzero) digits is 81648, while the sum is 39.

The square root of 66639702 is about 8163.3144004136. The cubic root of 66639702 is about 405.4254574829.

The spelling of 66639702 in words is "sixty-six million, six hundred thirty-nine thousand, seven hundred two".