66689430 has 64 divisors (see below), whose sum is σ = 170726400. Its totient is φ = 16623360.

The previous prime is 66689417. The next prime is 66689459. The reversal of 66689430 is 3498666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44290 + ... + 45770.

It is an arithmetic number, because the mean of its divisors is an integer number (2667600).

Almost surely, 2^66689430 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66689430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85363200).

66689430 is an abundant number, since it is smaller than the sum of its proper divisors (104036970).

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

66689430 is a wasteful number, since it uses less digits than its factorization.

66689430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1589.

The product of its (nonzero) digits is 186624, while the sum is 42.

The square root of 66689430 is about 8166.3596540931. The cubic root of 66689430 is about 405.5262781837.

The spelling of 66689430 in words is "sixty-six million, six hundred eighty-nine thousand, four hundred thirty".