66130221 has 16 divisors (see below), whose sum is σ = 97421184. Its totient is φ = 39688704.

The previous prime is 66130213. The next prime is 66130243. The reversal of 66130221 is 12203166.

It is a happy number.

66130221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66130221 - 2³ = 66130213 is a prime.

It is a super-2 number, since 2×66130221² = 8746412259017682, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66130201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27016 + ... + 29361.

It is an arithmetic number, because the mean of its divisors is an integer number (6088824).

Almost surely, 2^66130221 is an apocalyptic number.

It is an amenable number.

66130221 is a deficient number, since it is larger than the sum of its proper divisors (31290963).

66130221 is a wasteful number, since it uses less digits than its factorization.

66130221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56420.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 66130221 is about 8132.0490037874. The cubic root of 66130221 is about 404.3896124601.

Adding to 66130221 its reverse (12203166), we get a palindrome (78333387).

The spelling of 66130221 in words is "sixty-six million, one hundred thirty thousand, two hundred twenty-one".