66606620 has 48 divisors (see below), whose sum is σ = 151018560. Its totient is φ = 24600576.

The previous prime is 66606611. The next prime is 66606667. The reversal of 66606620 is 2660666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10844 + ... + 15836.

It is an arithmetic number, because the mean of its divisors is an integer number (3146220).

Almost surely, 2^66606620 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66606620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75509280).

66606620 is an abundant number, since it is smaller than the sum of its proper divisors (84411940).

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

66606620 is a wasteful number, since it uses less digits than its factorization.

66606620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5054 (or 5052 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 66606620 is about 8161.2878885627. The cubic root of 66606620 is about 405.3583578180.

The spelling of 66606620 in words is "sixty-six million, six hundred six thousand, six hundred twenty".