66726240 has 144 divisors (see below), whose sum is σ = 244590192. Its totient is φ = 15246336.

The previous prime is 66726221. The next prime is 66726259. The reversal of 66726240 is 4262766.

66726240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66726221) and next prime (66726259).

It is a super-2 number, since 2×66726240² = 8904782209075200, which contains 22 as substring.

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 23 ways as a sum of consecutive naturals, for example, 22102 + ... + 24938.

It is an arithmetic number, because the mean of its divisors is an integer number (1698543).

Almost surely, 2^66726240 is an apocalyptic number.

66726240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66726240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122295096).

66726240 is an abundant number, since it is smaller than the sum of its proper divisors (177863952).

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

66726240 is a wasteful number, since it uses less digits than its factorization.

66726240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2869 (or 2854 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 33.

The square root of 66726240 is about 8168.6131013777. The cubic root of 66726240 is about 405.6008760957.

It can be divided in two parts, 66726 and 240, that added together give a palindrome (66966).

The spelling of 66726240 in words is "sixty-six million, seven hundred twenty-six thousand, two hundred forty".