66442113 has 10 divisors (see below), whose sum is σ = 99253154. Its totient is φ = 44294688.

The previous prime is 66442109. The next prime is 66442133. The reversal of 66442113 is 31124466.

66442113 is a `hidden beast` number, since 6 + 644 + 2 + 1 + 13 = 666.

It can be written as a sum of positive squares in only one way, i.e., 55532304 + 10909809 = 7452^2 + 3303^2 .

It is not a de Polignac number, because 66442113 - 2² = 66442109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66442133) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 410056 + ... + 410217.

Almost surely, 2^66442113 is an apocalyptic number.

It is an amenable number.

66442113 is a deficient number, since it is larger than the sum of its proper divisors (32811041).

66442113 is an equidigital number, since it uses as much as digits as its factorization.

66442113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820285 (or 820276 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 66442113 is about 8151.2031627239. The cubic root of 66442113 is about 405.0243606746.

Adding to 66442113 its reverse (31124466), we get a palindrome (97566579).

The spelling of 66442113 in words is "sixty-six million, four hundred forty-two thousand, one hundred thirteen".