4185661 has 2 divisors, whose sum is σ = 4185662. Its totient is φ = 4185660.

The previous prime is 4185641. The next prime is 4185673. The reversal of 4185661 is 1665814.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3802500 + 383161 = 1950^2 + 619^2 .

It is a cyclic number.

It is not a de Polignac number, because 4185661 - 2¹³ = 4177469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4185641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2092830 + 2092831.

It is an arithmetic number, because the mean of its divisors is an integer number (2092831).

Almost surely, 2^4185661 is an apocalyptic number.

It is an amenable number.

4185661 is a deficient number, since it is larger than the sum of its proper divisors (1).

4185661 is an equidigital number, since it uses as much as digits as its factorization.

4185661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 31.

The square root of 4185661 is about 2045.8888044075. Note that the first 4 decimals coincide. The cubic root of 4185661 is about 161.1590445124.

The spelling of 4185661 in words is "four million, one hundred eighty-five thousand, six hundred sixty-one".