6660881 has 8 divisors (see below), whose sum is σ = 6854760. Its totient is φ = 6469632.

The previous prime is 6660859. The next prime is 6660911. The reversal of 6660881 is 1880666.

It can be written as a sum of positive squares in 4 ways, for example, as 3182656 + 3478225 = 1784^2 + 1865^2 .

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 6660881 - 2¹⁸ = 6398737 is a prime.

It is a super-2 number, since 2×6660881² = 88734671392322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6660781) 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, 5201 + ... + 6353.

It is an arithmetic number, because the mean of its divisors is an integer number (856845).

Almost surely, 2^6660881 is an apocalyptic number.

It is an amenable number.

6660881 is a deficient number, since it is larger than the sum of its proper divisors (193879).

6660881 is a wasteful number, since it uses less digits than its factorization.

6660881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1315.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 6660881 is about 2580.8682647512. The cubic root of 6660881 is about 188.1527448107.

The spelling of 6660881 in words is "six million, six hundred sixty thousand, eight hundred eighty-one".