6661081 has 4 divisors (see below), whose sum is σ = 7612672. Its totient is φ = 5709492.

The previous prime is 6661079. The next prime is 6661091. The reversal of 6661081 is 1801666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6661081 - 2¹ = 6661079 is a prime.

It is a super-2 number, since 2×6661081² = 88740000177122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6661021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 475785 + ... + 475798.

It is an arithmetic number, because the mean of its divisors is an integer number (1903168).

Almost surely, 2^6661081 is an apocalyptic number.

It is an amenable number.

6661081 is a deficient number, since it is larger than the sum of its proper divisors (951591).

6661081 is an equidigital number, since it uses as much as digits as its factorization.

6661081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 951590.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 6661081 is about 2580.9070111106. The cubic root of 6661081 is about 188.1546279536.

The spelling of 6661081 in words is "six million, six hundred sixty-one thousand, eighty-one".