66510660 has 48 divisors (see below), whose sum is σ = 186935616. Its totient is φ = 17668992.

The previous prime is 66510649. The next prime is 66510677. The reversal of 66510660 is 6601566.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 15022 + ... + 18938.

It is an arithmetic number, because the mean of its divisors is an integer number (3894492).

Almost surely, 2^66510660 is an apocalyptic number.

66510660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66510660 is an abundant number, since it is smaller than the sum of its proper divisors (120424956).

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

66510660 is a wasteful number, since it uses less digits than its factorization.

66510660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4212 (or 4210 counting only the distinct ones).

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

The square root of 66510660 is about 8155.4067954946. The cubic root of 66510660 is about 405.1635979820.

It can be divided in two parts, 665 and 10660, that added together give a triangular number (11325 = T₁₅₀).

The spelling of 66510660 in words is "sixty-six million, five hundred ten thousand, six hundred sixty".