66628560 has 80 divisors (see below), whose sum is σ = 209433024. Its totient is φ = 17519616.

The previous prime is 66628553. The next prime is 66628571. The reversal of 66628560 is 6582666.

It is a tau number, because it is divible by the number of its divisors (80).

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, 15619 + ... + 19421.

Almost surely, 2^66628560 is an apocalyptic number.

66628560 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66628560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104716512).

66628560 is an abundant number, since it is smaller than the sum of its proper divisors (142804464).

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

66628560 is a wasteful number, since it uses less digits than its factorization.

66628560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3892 (or 3886 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 39.

The square root of 66628560 is about 8162.6319284897. The cubic root of 66628560 is about 405.4028608321.

The spelling of 66628560 in words is "sixty-six million, six hundred twenty-eight thousand, five hundred sixty".