66211223 has 8 divisors (see below), whose sum is σ = 71471568. Its totient is φ = 60974784.

The previous prime is 66211207. The next prime is 66211237. The reversal of 66211223 is 32211266.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66211223 - 2⁴ = 66211207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66211253) 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, 11 + ... + 11507.

It is an arithmetic number, because the mean of its divisors is an integer number (8933946).

Almost surely, 2^66211223 is an apocalyptic number.

66211223 is a deficient number, since it is larger than the sum of its proper divisors (5260345).

66211223 is a wasteful number, since it uses less digits than its factorization.

66211223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11953.

The product of its digits is 864, while the sum is 23.

The square root of 66211223 is about 8137.0278972116. The cubic root of 66211223 is about 404.5546555206.

Adding to 66211223 its reverse (32211266), we get a palindrome (98422489).

The spelling of 66211223 in words is "sixty-six million, two hundred eleven thousand, two hundred twenty-three".