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231145660 = 225293710771
BaseRepresentation
bin11011100011100…
…00000010111100
3121002221102020101
431301300002330
5433133130120
634534130444
75504464024
oct1561600274
9532842211
10231145660
11109526179
12654b0a24
1338b708a5
14229aca84
151545c90a
hexdc700bc

231145660 has 48 divisors (see below), whose sum is σ = 515763360. Its totient is φ = 86849280.

The previous prime is 231145643. The next prime is 231145679. The reversal of 231145660 is 66541132.

231145660 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×2311456602 = 106856632273671200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16075 + ... + 26845.

It is an arithmetic number, because the mean of its divisors is an integer number (10745070).

Almost surely, 2231145660 is an apocalyptic number.

231145660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231145660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (257881680).

231145660 is an abundant number, since it is smaller than the sum of its proper divisors (284617700).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231145660 is a wasteful number, since it uses less digits than its factorization.

231145660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10846 (or 10844 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 231145660 is about 15203.4752606106. The cubic root of 231145660 is about 613.7081836112.

Adding to 231145660 its reverse (66541132), we get a palindrome (297686792).

The spelling of 231145660 in words is "two hundred thirty-one million, one hundred forty-five thousand, six hundred sixty".

Divisors: 1 2 4 5 10 20 29 37 58 74 116 145 148 185 290 370 580 740 1073 2146 4292 5365 10730 10771 21460 21542 43084 53855 107710 215420 312359 398527 624718 797054 1249436 1561795 1594108 1992635 3123590 3985270 6247180 7970540 11557283 23114566 46229132 57786415 115572830 231145660