66212224 has 32 divisors (see below), whose sum is σ = 142057440. Its totient is φ = 30558720.

The previous prime is 66212213. The next prime is 66212227. The reversal of 66212224 is 42221266.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66212227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18232 + ... + 21559.

It is an arithmetic number, because the mean of its divisors is an integer number (4439295).

Almost surely, 2^66212224 is an apocalyptic number.

66212224 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

66212224 is an abundant number, since it is smaller than the sum of its proper divisors (75845216).

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

66212224 is a wasteful number, since it uses less digits than its factorization.

66212224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39818 (or 39806 counting only the distinct ones).

The product of its digits is 2304, while the sum is 25.

The square root of 66212224 is about 8137.0894059240. The cubic root of 66212224 is about 404.5566942342.

The spelling of 66212224 in words is "sixty-six million, two hundred twelve thousand, two hundred twenty-four".