66374681 has 8 divisors (see below), whose sum is σ = 70466760. Its totient is φ = 62303488.

The previous prime is 66374663. The next prime is 66374683. The reversal of 66374681 is 18647366.

It can be written as a sum of positive squares in 4 ways, for example, as 6451600 + 59923081 = 2540^2 + 7741^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 66374681 - 2¹⁸ = 66112537 is a prime.

It is a super-2 number, since 2×66374681² = 8811196555703522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66374683) 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, 1595 + ... + 11631.

It is an arithmetic number, because the mean of its divisors is an integer number (8808345).

Almost surely, 2^66374681 is an apocalyptic number.

It is an amenable number.

66374681 is a deficient number, since it is larger than the sum of its proper divisors (4092079).

66374681 is a wasteful number, since it uses less digits than its factorization.

66374681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10443.

The product of its digits is 145152, while the sum is 41.

The square root of 66374681 is about 8147.0657908231. The cubic root of 66374681 is about 404.8872947578.

The spelling of 66374681 in words is "sixty-six million, three hundred seventy-four thousand, six hundred eighty-one".