6621161 has 8 divisors (see below), whose sum is σ = 6728904. Its totient is φ = 6514560.

The previous prime is 6621151. The next prime is 6621163. The reversal of 6621161 is 1611266.

6621161 = 1819² + 1820².

It can be written as a sum of positive squares in 4 ways, for example, as 295936 + 6325225 = 544^2 + 2515^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6621161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6621163) 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, 28301 + ... + 28533.

It is an arithmetic number, because the mean of its divisors is an integer number (841113).

Almost surely, 2^6621161 is an apocalyptic number.

6621161 is the 1820-th centered square number.

It is an amenable number.

6621161 is a deficient number, since it is larger than the sum of its proper divisors (107743).

6621161 is a wasteful number, since it uses less digits than its factorization.

6621161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 571.

The product of its digits is 432, while the sum is 23.

The square root of 6621161 is about 2573.1616738946. The cubic root of 6621161 is about 187.7780030134.

The spelling of 6621161 in words is "six million, six hundred twenty-one thousand, one hundred sixty-one".