66644113 has 2 divisors, whose sum is σ = 66644114. Its totient is φ = 66644112.

The previous prime is 66644111. The next prime is 66644159. The reversal of 66644113 is 31144666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66048129 + 595984 = 8127^2 + 772^2 .

It is a cyclic number.

It is not a de Polignac number, because 66644113 - 2¹ = 66644111 is a prime.

It is a super-3 number, since 3×66644113³ (a number of 24 digits) contains 333 as substring.

Together with 66644111, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66644111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33322056 + 33322057.

It is an arithmetic number, because the mean of its divisors is an integer number (33322057).

Almost surely, 2^66644113 is an apocalyptic number.

It is an amenable number.

66644113 is a deficient number, since it is larger than the sum of its proper divisors (1).

66644113 is an equidigital number, since it uses as much as digits as its factorization.

66644113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 31.

The square root of 66644113 is about 8163.5845680681. The cubic root of 66644113 is about 405.4344025621.

Adding to 66644113 its reverse (31144666), we get a palindrome (97788779).

The spelling of 66644113 in words is "sixty-six million, six hundred forty-four thousand, one hundred thirteen".