66956566 has 4 divisors (see below), whose sum is σ = 100434852. Its totient is φ = 33478282.

The previous prime is 66956537. The next prime is 66956573. The reversal of 66956566 is 66565966.

It is a semiprime because it is the product of two primes.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 16739140 + ... + 16739143.

It is an arithmetic number, because the mean of its divisors is an integer number (25108713).

Almost surely, 2^66956566 is an apocalyptic number.

66956566 is a deficient number, since it is larger than the sum of its proper divisors (33478286).

66956566 is a wasteful number, since it uses less digits than its factorization.

66956566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33478285.

The product of its digits is 1749600, while the sum is 49.

The square root of 66956566 is about 8182.6991879208. The cubic root of 66956566 is about 406.0670252614.

The spelling of 66956566 in words is "sixty-six million, nine hundred fifty-six thousand, five hundred sixty-six".