66440286 has 24 divisors (see below), whose sum is σ = 157041144. Its totient is φ = 20133360.

The previous prime is 66440273. The next prime is 66440287. The reversal of 66440286 is 68204466.

It is a happy number.

66440286 is a `hidden beast` number, since 6 + 644 + 0 + 2 + 8 + 6 = 666.

It is a zygodrome in base 3.

It is a self number, because there is not a number n which added to its sum of digits gives 66440286.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66440287) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 167581 + ... + 167976.

It is an arithmetic number, because the mean of its divisors is an integer number (6543381).

Almost surely, 2^66440286 is an apocalyptic number.

66440286 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66440286 is an abundant number, since it is smaller than the sum of its proper divisors (90600858).

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

66440286 is a wasteful number, since it uses less digits than its factorization.

66440286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335576 (or 335573 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 66440286 is about 8151.0910926084. The cubic root of 66440286 is about 405.0206482385.

It can be divided in two parts, 66 and 440286, that multiplied together give a triangular number (29058876 = T₇₆₂₃).

The spelling of 66440286 in words is "sixty-six million, four hundred forty thousand, two hundred eighty-six".