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218485 = 5371181
BaseRepresentation
bin110101010101110101
3102002201001
4311111311
523442420
64403301
71566661
oct652565
9362631
10218485
1113a173
12a6531
13785a7
14598a1
1544b0a
hex35575

218485 has 8 divisors (see below), whose sum is σ = 269496. Its totient is φ = 169920.

The previous prime is 218479. The next prime is 218509. The reversal of 218485 is 584812.

It can be written as a sum of positive squares in 4 ways, for example, as 111556 + 106929 = 334^2 + 327^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 218485 - 25 = 218453 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is a congruent number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 406 + ... + 775.

It is an arithmetic number, because the mean of its divisors is an integer number (33687).

2218485 is an apocalyptic number.

It is an amenable number.

218485 is a deficient number, since it is larger than the sum of its proper divisors (51011).

218485 is a wasteful number, since it uses less digits than its factorization.

218485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223.

The product of its digits is 2560, while the sum is 28.

The square root of 218485 is about 467.4237905798. The cubic root of 218485 is about 60.2292158127.

It can be divided in two parts, 218 and 485, that added together give a triangular number (703 = T37).

The spelling of 218485 in words is "two hundred eighteen thousand, four hundred eighty-five".

Divisors: 1 5 37 185 1181 5905 43697 218485