66123213 has 8 divisors (see below), whose sum is σ = 94946208. Its totient is φ = 40691184.

The previous prime is 66123209. The next prime is 66123257. The reversal of 66123213 is 31232166.

It is a happy number.

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

It is not a de Polignac number, because 66123213 - 2² = 66123209 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66123203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 847695 + ... + 847772.

It is an arithmetic number, because the mean of its divisors is an integer number (11868276).

Almost surely, 2^66123213 is an apocalyptic number.

It is an amenable number.

66123213 is a deficient number, since it is larger than the sum of its proper divisors (28822995).

66123213 is a wasteful number, since it uses less digits than its factorization.

66123213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1695483.

The product of its digits is 1296, while the sum is 24.

The square root of 66123213 is about 8131.6181046579. The cubic root of 66123213 is about 404.3753271985.

Adding to 66123213 its reverse (31232166), we get a palindrome (97355379).

The spelling of 66123213 in words is "sixty-six million, one hundred twenty-three thousand, two hundred thirteen".