66226213 has 4 divisors (see below), whose sum is σ = 66569548. Its totient is φ = 65882880.

The previous prime is 66226207. The next prime is 66226231. The reversal of 66226213 is 31262266.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13198689 + 53027524 = 3633^2 + 7282^2 .

It is a cyclic number.

It is not a de Polignac number, because 66226213 - 2²¹ = 64129061 is a prime.

It is a super-2 number, since 2×66226213² = 8771822576642738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66226313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171378 + ... + 171763.

It is an arithmetic number, because the mean of its divisors is an integer number (16642387).

Almost surely, 2^66226213 is an apocalyptic number.

It is an amenable number.

66226213 is a deficient number, since it is larger than the sum of its proper divisors (343335).

66226213 is a wasteful number, since it uses less digits than its factorization.

66226213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343334.

The product of its digits is 5184, while the sum is 28.

The square root of 66226213 is about 8137.9489430691. The cubic root of 66226213 is about 404.5851831584.

Adding to 66226213 its reverse (31262266), we get a palindrome (97488479).

The spelling of 66226213 in words is "sixty-six million, two hundred twenty-six thousand, two hundred thirteen".