66242181 has 8 divisors (see below), whose sum is σ = 88380160. Its totient is φ = 44132832.

The previous prime is 66242179. The next prime is 66242201. The reversal of 66242181 is 18124266.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66242181 - 2¹ = 66242179 is a prime.

It is a super-2 number, since 2×66242181² = 8776053087273522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66242161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1000 + ... + 11553.

It is an arithmetic number, because the mean of its divisors is an integer number (11047520).

Almost surely, 2^66242181 is an apocalyptic number.

It is an amenable number.

66242181 is a deficient number, since it is larger than the sum of its proper divisors (22137979).

66242181 is a wasteful number, since it uses less digits than its factorization.

66242181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14315.

The product of its digits is 4608, while the sum is 30.

The square root of 66242181 is about 8138.9299665251. The cubic root of 66242181 is about 404.6176974593.

The spelling of 66242181 in words is "sixty-six million, two hundred forty-two thousand, one hundred eighty-one".