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12705231 = 371155001
BaseRepresentation
bin110000011101…
…110111001111
3212220111022010
4300131313033
511223031411
61132152303
7212664330
oct60356717
925814263
1012705231
1171986a0
124308693
13282acb6
14198a287
1511ae7a6
hexc1ddcf

12705231 has 16 divisors (see below), whose sum is σ = 21120768. Its totient is φ = 6600000.

The previous prime is 12705229. The next prime is 12705271. The reversal of 12705231 is 13250721.

It is not a de Polignac number, because 12705231 - 21 = 12705229 is a prime.

It is a super-2 number, since 2×127052312 = 322845789526722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 12705198 and 12705207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12705211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27270 + ... + 27731.

It is an arithmetic number, because the mean of its divisors is an integer number (1320048).

Almost surely, 212705231 is an apocalyptic number.

12705231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12705231 is a deficient number, since it is larger than the sum of its proper divisors (8415537).

12705231 is a wasteful number, since it uses less digits than its factorization.

12705231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55022.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 12705231 is about 3564.4397876805. The cubic root of 12705231 is about 233.3426837523.

Adding to 12705231 its reverse (13250721), we get a palindrome (25955952).

Subtracting 12705231 from its reverse (13250721), we obtain a triangular number (545490 = T1044).

The spelling of 12705231 in words is "twelve million, seven hundred five thousand, two hundred thirty-one".

Divisors: 1 3 7 11 21 33 77 231 55001 165003 385007 605011 1155021 1815033 4235077 12705231