4081661 has 2 divisors, whose sum is σ = 4081662. Its totient is φ = 4081660.

The previous prime is 4081657. The next prime is 4081669. The reversal of 4081661 is 1661804.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3976036 + 105625 = 1994^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 4081661 - 2² = 4081657 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 4081661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4081669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2040830 + 2040831.

It is an arithmetic number, because the mean of its divisors is an integer number (2040831).

Almost surely, 2^4081661 is an apocalyptic number.

It is an amenable number.

4081661 is a deficient number, since it is larger than the sum of its proper divisors (1).

4081661 is an equidigital number, since it uses as much as digits as its factorization.

4081661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 4081661 is about 2020.3121046017. The cubic root of 4081661 is about 159.8130759772.

The spelling of 4081661 in words is "four million, eighty-one thousand, six hundred sixty-one".