66561508 has 24 divisors (see below), whose sum is σ = 126161280. Its totient is φ = 30544800.

The previous prime is 66561461. The next prime is 66561527. The reversal of 66561508 is 80516566.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

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, 5733 + ... + 12883.

It is an arithmetic number, because the mean of its divisors is an integer number (5256720).

Almost surely, 2^66561508 is an apocalyptic number.

It is an amenable number.

66561508 is a deficient number, since it is larger than the sum of its proper divisors (59599772).

66561508 is a wasteful number, since it uses less digits than its factorization.

66561508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7347 (or 7345 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 66561508 is about 8158.5236409537. The cubic root of 66561508 is about 405.2668220907.

The spelling of 66561508 in words is "sixty-six million, five hundred sixty-one thousand, five hundred eight".