66440808 has 96 divisors (see below), whose sum is σ = 206880960. Its totient is φ = 18869760.

The previous prime is 66440797. The next prime is 66440821. The reversal of 66440808 is 80804466.

66440808 is a `hidden beast` number, since 6 + 644 + 0 + 8 + 0 + 8 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 121191 + ... + 121737.

It is an arithmetic number, because the mean of its divisors is an integer number (2155010).

Almost surely, 2^66440808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66440808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103440480).

66440808 is an abundant number, since it is smaller than the sum of its proper divisors (140440152).

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

66440808 is a wasteful number, since it uses less digits than its factorization.

66440808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 807 (or 800 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 66440808 is about 8151.1231127986. The cubic root of 66440808 is about 405.0217089415.

The spelling of 66440808 in words is "sixty-six million, four hundred forty thousand, eight hundred eight".