66373440 has 336 divisors, whose sum is σ = 262688832. Its totient is φ = 14106624.

The previous prime is 66373369. The next prime is 66373453. The reversal of 66373440 is 4437366.

66373440 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 (336).

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 47 ways as a sum of consecutive naturals, for example, 799639 + ... + 799721.

It is an arithmetic number, because the mean of its divisors is an integer number (781812).

Almost surely, 2^66373440 is an apocalyptic number.

66373440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

66373440 is the 4704-th octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66373440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131344416).

66373440 is an abundant number, since it is smaller than the sum of its proper divisors (196315392).

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

66373440 is a wasteful number, since it uses less digits than its factorization.

66373440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 33.

The square root of 66373440 is about 8146.9896280774. The cubic root of 66373440 is about 404.8847713645.

The spelling of 66373440 in words is "sixty-six million, three hundred seventy-three thousand, four hundred forty".