66409056 has 72 divisors (see below), whose sum is σ = 215835984. Its totient is φ = 18973440.

The previous prime is 66409019. The next prime is 66409061. The reversal of 66409056 is 65090466.

It is a happy number.

66409056 is a `hidden beast` number, since 6 + 640 + 9 + 0 + 5 + 6 = 666.

66409056 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×66409056² = 8820325437622272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 66409056.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 14455 + ... + 18486.

It is an arithmetic number, because the mean of its divisors is an integer number (2997722).

Almost surely, 2^66409056 is an apocalyptic number.

It is an amenable number.

66409056 is an abundant number, since it is smaller than the sum of its proper divisors (149426928).

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

66409056 is a wasteful number, since it uses less digits than its factorization.

66409056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32964 (or 32953 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 66409056 is about 8149.1751729853. The cubic root of 66409056 is about 404.9571788288.

The spelling of 66409056 in words is "sixty-six million, four hundred nine thousand, fifty-six".