666571081 has 8 divisors (see below), whose sum is σ = 727892928. Its totient is φ = 605370000.

The previous prime is 666571069. The next prime is 666571093. The reversal of 666571081 is 180175666.

666571081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (666571069) and next prime (666571093).

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 666571081 - 2¹³ = 666562889 is a prime.

It is a super-2 number, since 2×666571081² = 888634012051017122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666571001) 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, 18445 + ... + 40906.

It is an arithmetic number, because the mean of its divisors is an integer number (90986616).

Almost surely, 2^666571081 is an apocalyptic number.

It is an amenable number.

666571081 is a deficient number, since it is larger than the sum of its proper divisors (61321847).

666571081 is a wasteful number, since it uses less digits than its factorization.

666571081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60383.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 666571081 is about 25818.0378998870. The cubic root of 666571081 is about 873.5387118552.

The spelling of 666571081 in words is "six hundred sixty-six million, five hundred seventy-one thousand, eighty-one".