442781 has 2 divisors, whose sum is σ = 442782. Its totient is φ = 442780.

The previous prime is 442777. The next prime is 442789. The reversal of 442781 is 187244.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 225625 + 217156 = 475^2 + 466^2 .

It is a cyclic number.

It is not a de Polignac number, because 442781 - 2² = 442777 is a prime.

It is a super-2 number, since 2×442781² = 392110027922, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 442781.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 442781.

It is not a weakly prime, because it can be changed into another prime (442789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 221390 + 221391.

It is an arithmetic number, because the mean of its divisors is an integer number (221391).

2⁴⁴²⁷⁸¹ is an apocalyptic number.

It is an amenable number.

442781 is a deficient number, since it is larger than the sum of its proper divisors (1).

442781 is an equidigital number, since it uses as much as digits as its factorization.

442781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1792, while the sum is 26.

The square root of 442781 is about 665.4179137955. The cubic root of 442781 is about 76.2189553815.

The spelling of 442781 in words is "four hundred forty-two thousand, seven hundred eighty-one".