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33813 = 3213172
BaseRepresentation
bin1000010000010101
31201101100
420100111
52040223
6420313
7200403
oct102025
951340
1033813
112344a
1217699
1312510
14c473
15a043
hex8415

33813 has 18 divisors (see below), whose sum is σ = 55874. Its totient is φ = 19584.

The previous prime is 33811. The next prime is 33827. The reversal of 33813 is 31833.

It can be written as a sum of positive squares in 3 ways, for example, as 7569 + 26244 = 87^2 + 162^2 .

It is not a de Polignac number, because 33813 - 21 = 33811 is a prime.

It is a super-2 number, since 2×338132 = 2286637938, which contains 22 as substring.

33813 is a lucky number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33811) 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 in 17 ways as a sum of consecutive naturals, for example, 1981 + ... + 1997.

233813 is an apocalyptic number.

It is an amenable number.

33813 is a deficient number, since it is larger than the sum of its proper divisors (22061).

33813 is a wasteful number, since it uses less digits than its factorization.

33813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53 (or 33 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 33813 is about 183.8831150487. The cubic root of 33813 is about 32.3366159089.

It can be divided in two parts, 338 and 13, that added together give a triangular number (351 = T26).

The spelling of 33813 in words is "thirty-three thousand, eight hundred thirteen".