66442111 has 4 divisors (see below), whose sum is σ = 66617800. Its totient is φ = 66266424.

The previous prime is 66442109. The next prime is 66442133. The reversal of 66442111 is 11124466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66442111 - 2¹ = 66442109 is a prime.

It is a super-2 number, since 2×66442111² = 8829108228272642, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66442151) 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, 87276 + ... + 88033.

It is an arithmetic number, because the mean of its divisors is an integer number (16654450).

Almost surely, 2^66442111 is an apocalyptic number.

66442111 is a deficient number, since it is larger than the sum of its proper divisors (175689).

66442111 is a wasteful number, since it uses less digits than its factorization.

66442111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175688.

The product of its digits is 1152, while the sum is 25.

The square root of 66442111 is about 8151.2030400426. The cubic root of 66442111 is about 405.0243566107.

Adding to 66442111 its reverse (11124466), we get a palindrome (77566577).

The spelling of 66442111 in words is "sixty-six million, four hundred forty-two thousand, one hundred eleven".