66448881 has 6 divisors (see below), whose sum is σ = 95981730. Its totient is φ = 44299248.

The previous prime is 66448853. The next prime is 66448919. The reversal of 66448881 is 18884466.

It can be written as a sum of positive squares in only one way, i.e., 37933281 + 28515600 = 6159^2 + 5340^2 .

It is not a de Polignac number, because 66448881 - 2⁵ = 66448849 is a prime.

It is a super-2 number, since 2×66448881² = 8830907572304322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66447881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3691596 + ... + 3691613.

It is an arithmetic number, because the mean of its divisors is an integer number (15996955).

Almost surely, 2^66448881 is an apocalyptic number.

It is an amenable number.

66448881 is a deficient number, since it is larger than the sum of its proper divisors (29532849).

66448881 is a wasteful number, since it uses less digits than its factorization.

66448881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7383215 (or 7383212 counting only the distinct ones).

The product of its digits is 294912, while the sum is 45.

The square root of 66448881 is about 8151.6183055882. The cubic root of 66448881 is about 405.0381125541.

The spelling of 66448881 in words is "sixty-six million, four hundred forty-eight thousand, eight hundred eighty-one".