66345440 has 96 divisors (see below), whose sum is σ = 184089024. Its totient is φ = 22118400.

The previous prime is 66345439. The next prime is 66345443. The reversal of 66345440 is 4454366.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 66345397 and 66345406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66345443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40640 + ... + 42240.

It is an arithmetic number, because the mean of its divisors is an integer number (1917594).

Almost surely, 2^66345440 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 66345440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92044512).

66345440 is an abundant number, since it is smaller than the sum of its proper divisors (117743584).

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

66345440 is a wasteful number, since it uses less digits than its factorization.

66345440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1660 (or 1652 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 32.

The square root of 66345440 is about 8145.2710206598. The cubic root of 66345440 is about 404.8278290689.

The spelling of 66345440 in words is "sixty-six million, three hundred forty-five thousand, four hundred forty".