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1808801 is a prime number
BaseRepresentation
bin110111001100110100001
310101220012122
412321212201
5430340201
6102434025
721242321
oct6714641
93356178
101808801
111025a85
12732915
134b43c7
14351281
1525ae1b
hex1b99a1

1808801 has 2 divisors, whose sum is σ = 1808802. Its totient is φ = 1808800.

The previous prime is 1808773. The next prime is 1808803. The reversal of 1808801 is 1088081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1628176 + 180625 = 1276^2 + 425^2 .

It is an emirp because it is prime and its reverse (1088081) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-1808801 is a prime.

It is a super-2 number, since 2×18088012 = 6543522115202, which contains 22 as substring.

Together with 1808803, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p135683 and since 1808801 and 135683 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (1808803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 904400 + 904401.

It is an arithmetic number, because the mean of its divisors is an integer number (904401).

21808801 is an apocalyptic number.

It is an amenable number.

1808801 is a deficient number, since it is larger than the sum of its proper divisors (1).

1808801 is an equidigital number, since it uses as much as digits as its factorization.

1808801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 512, while the sum is 26.

The square root of 1808801 is about 1344.9167260466. The cubic root of 1808801 is about 121.8419749221.

The spelling of 1808801 in words is "one million, eight hundred eight thousand, eight hundred one".