66164240 has 40 divisors (see below), whose sum is σ = 154376280. Its totient is φ = 26372096.

The previous prime is 66164239. The next prime is 66164243. The reversal of 66164240 is 4246166.

It can be written as a sum of positive squares in 4 ways, for example, as 99856 + 66064384 = 316^2 + 8128^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (66164243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24056 + ... + 26664.

It is an arithmetic number, because the mean of its divisors is an integer number (3859407).

Almost surely, 2^66164240 is an apocalyptic number.

It is an amenable number.

66164240 is an abundant number, since it is smaller than the sum of its proper divisors (88212040).

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

66164240 is a wasteful number, since it uses less digits than its factorization.

66164240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2939 (or 2933 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 66164240 is about 8134.1403971163. The cubic root of 66164240 is about 404.4589432024.

The spelling of 66164240 in words is "sixty-six million, one hundred sixty-four thousand, two hundred forty".