4191581 has 2 divisors, whose sum is σ = 4191582. Its totient is φ = 4191580.

The previous prime is 4191563. The next prime is 4191599. The reversal of 4191581 is 1851914.

It is a balanced prime because it is at equal distance from previous prime (4191563) and next prime (4191599).

It can be written as a sum of positive squares in only one way, i.e., 2325625 + 1865956 = 1525^2 + 1366^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4191581 is a prime.

It is a super-2 number, since 2×4191581² = 35138702559122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4191521) 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, 2095790 + 2095791.

It is an arithmetic number, because the mean of its divisors is an integer number (2095791).

Almost surely, 2^4191581 is an apocalyptic number.

It is an amenable number.

4191581 is a deficient number, since it is larger than the sum of its proper divisors (1).

4191581 is an equidigital number, since it uses as much as digits as its factorization.

4191581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 29.

The square root of 4191581 is about 2047.3350971446. The cubic root of 4191581 is about 161.2349872849.

The spelling of 4191581 in words is "four million, one hundred ninety-one thousand, five hundred eighty-one".