4243781 has 2 divisors, whose sum is σ = 4243782. Its totient is φ = 4243780.

The previous prime is 4243747. The next prime is 4243793. The reversal of 4243781 is 1873424.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2353156 + 1890625 = 1534^2 + 1375^2 .

It is a cyclic number.

It is not a de Polignac number, because 4243781 - 2¹⁴ = 4227397 is a prime.

It is a super-2 number, since 2×4243781² = 36019354351922, which contains 22 as substring.

It is a d-powerful number, because it can be written as 4⁷ + 2⁵ + 4¹¹ + 3⁵ + 7² + 8⁵ + 1 .

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4243711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2121890 + 2121891.

It is an arithmetic number, because the mean of its divisors is an integer number (2121891).

Almost surely, 2^4243781 is an apocalyptic number.

It is an amenable number.

4243781 is a deficient number, since it is larger than the sum of its proper divisors (1).

4243781 is an equidigital number, since it uses as much as digits as its factorization.

4243781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 29.

The square root of 4243781 is about 2060.0439315704. The cubic root of 4243781 is about 161.9015430801.

The spelling of 4243781 in words is "four million, two hundred forty-three thousand, seven hundred eighty-one".