6661161 has 36 divisors (see below), whose sum is σ = 11063052. Its totient is φ = 3838464.

The previous prime is 6661157. The next prime is 6661189. The reversal of 6661161 is 1611666.

It can be written as a sum of positive squares in 6 ways, for example, as 1115136 + 5546025 = 1056^2 + 2355^2 .

It is not a de Polignac number, because 6661161 - 2² = 6661157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6661111) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 33715 + ... + 33911.

It is an arithmetic number, because the mean of its divisors is an integer number (307307).

Almost surely, 2^6661161 is an apocalyptic number.

It is an amenable number.

6661161 is a deficient number, since it is larger than the sum of its proper divisors (4401891).

6661161 is a wasteful number, since it uses less digits than its factorization.

6661161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 230 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 6661161 is about 2580.9225094915. The cubic root of 6661161 is about 188.1553812002.

The spelling of 6661161 in words is "six million, six hundred sixty-one thousand, one hundred sixty-one".