66215232 has 140 divisors (see below), whose sum is σ = 200815956. Its totient is φ = 21565440.

The previous prime is 66215213. The next prime is 66215249. The reversal of 66215232 is 23251266.

66215232 is a `hidden beast` number, since 6 + 621 + 5 + 2 + 32 = 666.

66215232 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 48776256 + 17438976 = 6984^2 + 4176^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 66215196 and 66215205.

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 19 ways as a sum of consecutive naturals, for example, 274632 + ... + 274872.

Almost surely, 2^66215232 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 66215232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100407978).

66215232 is an abundant number, since it is smaller than the sum of its proper divisors (134600724).

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

66215232 is a wasteful number, since it uses less digits than its factorization.

66215232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318 (or 299 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 66215232 is about 8137.2742364996. The cubic root of 66215232 is about 404.5628204349.

Adding to 66215232 its reverse (23251266), we get a palindrome (89466498).

The spelling of 66215232 in words is "sixty-six million, two hundred fifteen thousand, two hundred thirty-two".