66558380 has 24 divisors (see below), whose sum is σ = 159740448. Its totient is φ = 22819968.

The previous prime is 66558379. The next prime is 66558397. The reversal of 66558380 is 8385566.

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 7 ways as a sum of consecutive naturals, for example, 237569 + ... + 237848.

It is an arithmetic number, because the mean of its divisors is an integer number (6655852).

Almost surely, 2^66558380 is an apocalyptic number.

It is an amenable number.

66558380 is an abundant number, since it is smaller than the sum of its proper divisors (93182068).

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

66558380 is a wasteful number, since it uses less digits than its factorization.

66558380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475433 (or 475431 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 66558380 is about 8158.3319373509. The cubic root of 66558380 is about 405.2604736043.

The spelling of 66558380 in words is "sixty-six million, five hundred fifty-eight thousand, three hundred eighty".