4381681 has 2 divisors, whose sum is σ = 4381682. Its totient is φ = 4381680.

The previous prime is 4381667. The next prime is 4381693. The reversal of 4381681 is 1861834.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3182656 + 1199025 = 1784^2 + 1095^2 .

It is a cyclic number.

It is not a de Polignac number, because 4381681 - 2¹³ = 4373489 is a prime.

It is a super-2 number, since 2×4381681² = 38398256771522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4385681) 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, 2190840 + 2190841.

It is an arithmetic number, because the mean of its divisors is an integer number (2190841).

Almost surely, 2^4381681 is an apocalyptic number.

It is an amenable number.

4381681 is a deficient number, since it is larger than the sum of its proper divisors (1).

4381681 is an equidigital number, since it uses as much as digits as its factorization.

4381681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4608, while the sum is 31.

The square root of 4381681 is about 2093.2465215545. The cubic root of 4381681 is about 163.6365264776.

The spelling of 4381681 in words is "four million, three hundred eighty-one thousand, six hundred eighty-one".