66841668 has 18 divisors (see below), whose sum is σ = 168960974. Its totient is φ = 22280544.

The previous prime is 66841613. The next prime is 66841681. The reversal of 66841668 is 86614866.

It can be written as a sum of positive squares in only one way, i.e., 56070144 + 10771524 = 7488^2 + 3282^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-3 number, since 3×66841668³ (a number of 24 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 928321 + ... + 928392.

Almost surely, 2^66841668 is an apocalyptic number.

It is an amenable number.

66841668 is an abundant number, since it is smaller than the sum of its proper divisors (102119306).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66841668 is a wasteful number, since it uses less digits than its factorization.

66841668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1856723 (or 1856718 counting only the distinct ones).

The product of its digits is 331776, while the sum is 45.

The square root of 66841668 is about 8175.6753849453. The cubic root of 66841668 is about 405.8346208593.

The spelling of 66841668 in words is "sixty-six million, eight hundred forty-one thousand, six hundred sixty-eight".