666381371 has 8 divisors (see below), whose sum is σ = 669696720. Its totient is φ = 663075072.

The previous prime is 666381361. The next prime is 666381377. The reversal of 666381371 is 173183666.

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 666381371 - 2¹⁰ = 666380347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666381377) 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, 179591 + ... + 183263.

It is an arithmetic number, because the mean of its divisors is an integer number (83712090).

Almost surely, 2^666381371 is an apocalyptic number.

666381371 is a deficient number, since it is larger than the sum of its proper divisors (3315349).

666381371 is a wasteful number, since it uses less digits than its factorization.

666381371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4525.

The product of its digits is 108864, while the sum is 41.

The square root of 666381371 is about 25814.3636566931. The cubic root of 666381371 is about 873.4558325956.

The spelling of 666381371 in words is "six hundred sixty-six million, three hundred eighty-one thousand, three hundred seventy-one".