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BaseRepresentation
bin11100001001
32110201
4130021
524201
612201
75152
oct3411
92421
101801
111398
121061
13a87
14929
15801
hex709

1801 has 2 divisors, whose sum is σ = 1802. Its totient is φ = 1800.

The previous prime is 1789. The next prime is 1811. The reversal of 1801 is 1081.

1801 is nontrivially palindromic in base 14.

It is an a-pointer prime, because the next prime (1811) can be obtained adding 1801 to its sum of digits (10).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1225 + 576 = 35^2 + 24^2 .

It is a cyclic number.

It is not a de Polignac number, because 1801 - 29 = 1289 is a prime.

It is a Chen prime.

1801 is an undulating number in base 14.

1801 is a lucky number.

It is a nialpdrome in base 13.

It is not a weakly prime, because it can be changed into another prime (1811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 900 + 901.

It is an arithmetic number, because the mean of its divisors is an integer number (901).

1801 is the 25-th hex number.

It is an amenable number.

1801 is a deficient number, since it is larger than the sum of its proper divisors (1).

1801 is an equidigital number, since it uses as much as digits as its factorization.

1801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1801 is about 42.4381903478. The cubic root of 1801 is about 12.1666562415.

Adding to 1801 its reverse (1081), we get a palindrome (2882).

It can be divided in two parts, 180 and 1, that added together give a palindrome (181).

The spelling of 1801 in words is "one thousand, eight hundred one".