66866660 has 24 divisors (see below), whose sum is σ = 160480320. Its totient is φ = 22925664.

The previous prime is 66866629. The next prime is 66866669. The reversal of 66866660 is 6666866.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (66866669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238670 + ... + 238949.

It is an arithmetic number, because the mean of its divisors is an integer number (6686680).

Almost surely, 2^66866660 is an apocalyptic number.

It is an amenable number.

66866660 is an abundant number, since it is smaller than the sum of its proper divisors (93613660).

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

66866660 is a wasteful number, since it uses less digits than its factorization.

66866660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477635 (or 477633 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 44.

The square root of 66866660 is about 8177.2036785199. The cubic root of 66866660 is about 405.8851948765.

The spelling of 66866660 in words is "sixty-six million, eight hundred sixty-six thousand, six hundred sixty".