66549988 has 6 divisors (see below), whose sum is σ = 116462486. Its totient is φ = 33274992.

The previous prime is 66549947. The next prime is 66549991. The reversal of 66549988 is 88994566.

It can be written as a sum of positive squares in only one way, i.e., 46676224 + 19873764 = 6832^2 + 4458^2 .

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, 8318745 + ... + 8318752.

Almost surely, 2^66549988 is an apocalyptic number.

It is an amenable number.

66549988 is a deficient number, since it is larger than the sum of its proper divisors (49912498).

66549988 is a wasteful number, since it uses less digits than its factorization.

66549988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16637501 (or 16637499 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 55.

The square root of 66549988 is about 8157.8176003144. The cubic root of 66549988 is about 405.2434404932.

It can be divided in two parts, 665 and 49988, that added together give a cube (50653 = 37³).

The spelling of 66549988 in words is "sixty-six million, five hundred forty-nine thousand, nine hundred eighty-eight".