66550240 has 96 divisors (see below), whose sum is σ = 170644320. Its totient is φ = 24428544.

The previous prime is 66550219. The next prime is 66550241. The reversal of 66550240 is 4205566.

It is a junction number, because it is equal to n+sod(n) for n = 66550199 and 66550208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66550241) 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 15 ways as a sum of consecutive naturals, for example, 116676 + ... + 117244.

It is an arithmetic number, because the mean of its divisors is an integer number (1777545).

Almost surely, 2^66550240 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 66550240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85322160).

66550240 is an abundant number, since it is smaller than the sum of its proper divisors (104094080).

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

66550240 is a wasteful number, since it uses less digits than its factorization.

66550240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644 (or 636 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 66550240 is about 8157.8330456071. The cubic root of 66550240 is about 405.2439519945.

It can be divided in two parts, 665 and 50240, that added together give a palindrome (50905).

The spelling of 66550240 in words is "sixty-six million, five hundred fifty thousand, two hundred forty".