66610660 has 24 divisors (see below), whose sum is σ = 140035896. Its totient is φ = 26615040.

The previous prime is 66610657. The next prime is 66610679. The reversal of 66610660 is 6601666.

It can be written as a sum of positive squares in 4 ways, for example, as 1582564 + 65028096 = 1258^2 + 8064^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33864 + ... + 35776.

It is an arithmetic number, because the mean of its divisors is an integer number (5834829).

Almost surely, 2^66610660 is an apocalyptic number.

It is an amenable number.

66610660 is an abundant number, since it is smaller than the sum of its proper divisors (73425236).

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

66610660 is a wasteful number, since it uses less digits than its factorization.

66610660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3663 (or 3661 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 66610660 is about 8161.5353947649. The cubic root of 66610660 is about 405.3665532729.

The spelling of 66610660 in words is "sixty-six million, six hundred ten thousand, six hundred sixty".