66213118 has 4 divisors (see below), whose sum is σ = 99319680. Its totient is φ = 33106558.

The previous prime is 66213107. The next prime is 66213127. The reversal of 66213118 is 81131266.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81131266 = 2 ⋅40565633.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 16553278 + ... + 16553281.

It is an arithmetic number, because the mean of its divisors is an integer number (24829920).

Almost surely, 2^66213118 is an apocalyptic number.

66213118 is a deficient number, since it is larger than the sum of its proper divisors (33106562).

66213118 is a wasteful number, since it uses less digits than its factorization.

66213118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33106561.

The product of its digits is 1728, while the sum is 28.

The square root of 66213118 is about 8137.1443393859. The cubic root of 66213118 is about 404.5585150061.

The spelling of 66213118 in words is "sixty-six million, two hundred thirteen thousand, one hundred eighteen".