66213140 has 48 divisors (see below), whose sum is σ = 160406400. Its totient is φ = 22488192.

The previous prime is 66213131. The next prime is 66213187. The reversal of 66213140 is 4131266.

It is a happy number.

66213140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 15 ways as a sum of consecutive naturals, for example, 13091 + ... + 17429.

It is an arithmetic number, because the mean of its divisors is an integer number (3341800).

Almost surely, 2^66213140 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 66213140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80203200).

66213140 is an abundant number, since it is smaller than the sum of its proper divisors (94193260).

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

66213140 is a wasteful number, since it uses less digits than its factorization.

66213140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4464 (or 4462 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 66213140 is about 8137.1456912114. The cubic root of 66213140 is about 404.5585598123.

The spelling of 66213140 in words is "sixty-six million, two hundred thirteen thousand, one hundred forty".