66405544 has 16 divisors (see below), whose sum is σ = 125421300. Its totient is φ = 32959872.

The previous prime is 66405539. The next prime is 66405601. The reversal of 66405544 is 44550466.

66405544 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 62252100 + 4153444 = 7890^2 + 2038^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29199 + ... + 31390.

Almost surely, 2^66405544 is an apocalyptic number.

It is an amenable number.

66405544 is a deficient number, since it is larger than the sum of its proper divisors (59015756).

66405544 is a wasteful number, since it uses less digits than its factorization.

66405544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60732 (or 60728 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 34.

The square root of 66405544 is about 8148.9596882056. The cubic root of 66405544 is about 404.9500400701.

The spelling of 66405544 in words is "sixty-six million, four hundred five thousand, five hundred forty-four".