66544842 has 96 divisors (see below), whose sum is σ = 174206592. Its totient is φ = 16765056.

The previous prime is 66544801. The next prime is 66544843. The reversal of 66544842 is 24844566.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 66544842.

It is not an unprimeable number, because it can be changed into a prime (66544843) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 87528 + ... + 88284.

It is an arithmetic number, because the mean of its divisors is an integer number (1814652).

Almost surely, 2^66544842 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66544842, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87103296).

66544842 is an abundant number, since it is smaller than the sum of its proper divisors (107661750).

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

66544842 is a wasteful number, since it uses less digits than its factorization.

66544842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812 (or 805 counting only the distinct ones).

The product of its digits is 184320, while the sum is 39.

The square root of 66544842 is about 8157.5021912348. The cubic root of 66544842 is about 405.2329950293.

The spelling of 66544842 in words is "sixty-six million, five hundred forty-four thousand, eight hundred forty-two".