285641 has 2 divisors, whose sum is σ = 285642. Its totient is φ = 285640.

The previous prime is 285631. The next prime is 285643. The reversal of 285641 is 146582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198025 + 87616 = 445^2 + 296^2 .

It is a cyclic number.

It is not a de Polignac number, because 285641 - 2¹⁴ = 269257 is a prime.

Together with 285643, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p₂₄₈₉₃ and since 285641 and 24893 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 285641.

It is not a weakly prime, because it can be changed into another prime (285643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 142820 + 142821.

It is an arithmetic number, because the mean of its divisors is an integer number (142821).

2²⁸⁵⁶⁴¹ is an apocalyptic number.

It is an amenable number.

285641 is a deficient number, since it is larger than the sum of its proper divisors (1).

285641 is an equidigital number, since it uses as much as digits as its factorization.

285641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 26.

The square root of 285641 is about 534.4539269198. The cubic root of 285641 is about 65.8577438007.

The spelling of 285641 in words is "two hundred eighty-five thousand, six hundred forty-one".