66412213 has 4 divisors (see below), whose sum is σ = 75899680. Its totient is φ = 56924748.

The previous prime is 66412207. The next prime is 66412243. The reversal of 66412213 is 31221466.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31221466 = 2 ⋅15610733.

It is a cyclic number.

It is not a de Polignac number, because 66412213 - 2⁹ = 66411701 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 (66412243) 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, 4743723 + ... + 4743736.

It is an arithmetic number, because the mean of its divisors is an integer number (18974920).

Almost surely, 2^66412213 is an apocalyptic number.

It is an amenable number.

66412213 is a deficient number, since it is larger than the sum of its proper divisors (9487467).

66412213 is an equidigital number, since it uses as much as digits as its factorization.

66412213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9487466.

The product of its digits is 1728, while the sum is 25.

The square root of 66412213 is about 8149.3688712685. The cubic root of 66412213 is about 404.9635957727.

Adding to 66412213 its reverse (31221466), we get a palindrome (97633679).

The spelling of 66412213 in words is "sixty-six million, four hundred twelve thousand, two hundred thirteen".