66133213 has 4 divisors (see below), whose sum is σ = 70023420. Its totient is φ = 62243008.

The previous prime is 66133189. The next prime is 66133219. The reversal of 66133213 is 31233166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31233166 = 2 ⋅15616583.

It can be written as a sum of positive squares in 2 ways, for example, as 36517849 + 29615364 = 6043^2 + 5442^2 .

It is a cyclic number.

It is not a de Polignac number, because 66133213 - 2⁹ = 66132701 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 (66133219) 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, 1945078 + ... + 1945111.

It is an arithmetic number, because the mean of its divisors is an integer number (17505855).

Almost surely, 2^66133213 is an apocalyptic number.

It is an amenable number.

66133213 is a deficient number, since it is larger than the sum of its proper divisors (3890207).

66133213 is a wasteful number, since it uses less digits than its factorization.

66133213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3890206.

The product of its digits is 1944, while the sum is 25.

The square root of 66133213 is about 8132.2329651824. The cubic root of 66133213 is about 404.3957111113.

Adding to 66133213 its reverse (31233166), we get a palindrome (97366379).

The spelling of 66133213 in words is "sixty-six million, one hundred thirty-three thousand, two hundred thirteen".