4065781 has 2 divisors, whose sum is σ = 4065782. Its totient is φ = 4065780.

The previous prime is 4065773. The next prime is 4065821. The reversal of 4065781 is 1875604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2722500 + 1343281 = 1650^2 + 1159^2 .

It is a cyclic number.

It is not a de Polignac number, because 4065781 - 2³ = 4065773 is a prime.

It is a super-2 number, since 2×4065781² = 33061150279922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4065701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2032890 + 2032891.

It is an arithmetic number, because the mean of its divisors is an integer number (2032891).

Almost surely, 2^4065781 is an apocalyptic number.

It is an amenable number.

4065781 is a deficient number, since it is larger than the sum of its proper divisors (1).

4065781 is an equidigital number, since it uses as much as digits as its factorization.

4065781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 4065781 is about 2016.3781887335. The cubic root of 4065781 is about 159.6055518030.

The spelling of 4065781 in words is "four million, sixty-five thousand, seven hundred eighty-one".