66400288 has 24 divisors (see below), whose sum is σ = 137607120. Its totient is φ = 31452480.

The previous prime is 66400277. The next prime is 66400297. The reversal of 66400288 is 88200466.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53998 + ... + 55213.

It is an arithmetic number, because the mean of its divisors is an integer number (5733630).

Almost surely, 2^66400288 is an apocalyptic number.

It is an amenable number.

66400288 is an abundant number, since it is smaller than the sum of its proper divisors (71206832).

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

66400288 is a wasteful number, since it uses less digits than its factorization.

66400288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109240 (or 109232 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 66400288 is about 8148.6371866712. The cubic root of 66400288 is about 404.9393558539.

The spelling of 66400288 in words is "sixty-six million, four hundred thousand, two hundred eighty-eight".