66164238 has 144 divisors (see below), whose sum is σ = 183905280. Its totient is φ = 16803072.

The previous prime is 66164183. The next prime is 66164239. The reversal of 66164238 is 83246166.

66164238 is a `hidden beast` number, since 6 + 6 + 1 + 642 + 3 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66164239) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 837483 + ... + 837561.

It is an arithmetic number, because the mean of its divisors is an integer number (1277120).

Almost surely, 2^66164238 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66164238, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91952640).

66164238 is an abundant number, since it is smaller than the sum of its proper divisors (117741042).

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

66164238 is a wasteful number, since it uses less digits than its factorization.

66164238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151 (or 131 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 66164238 is about 8134.1402741777. The cubic root of 66164238 is about 404.4589391271.

The spelling of 66164238 in words is "sixty-six million, one hundred sixty-four thousand, two hundred thirty-eight".