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231430220 = 22571819133
BaseRepresentation
bin11011100101101…
…01100001001100
3121010110212120122
431302311201030
5433221231340
634544204112
75510060450
oct1562654114
9533425518
10231430220
111096aaa4a
1265609638
1338c40278
1422a44660
15154b6db5
hexdcb584c

231430220 has 48 divisors (see below), whose sum is σ = 558562368. Its totient is φ = 78900480.

The previous prime is 231430219. The next prime is 231430247. The reversal of 231430220 is 22034132.

231430220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20774 + ... + 29906.

It is an arithmetic number, because the mean of its divisors is an integer number (11636716).

Almost surely, 2231430220 is an apocalyptic number.

231430220 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 231430220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (279281184).

231430220 is an abundant number, since it is smaller than the sum of its proper divisors (327132148).

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

231430220 is a wasteful number, since it uses less digits than its factorization.

231430220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9330 (or 9328 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 231430220 is about 15212.8307687951. The cubic root of 231430220 is about 613.9599226884.

Adding to 231430220 its reverse (22034132), we get a palindrome (253464352).

The spelling of 231430220 in words is "two hundred thirty-one million, four hundred thirty thousand, two hundred twenty".

Divisors: 1 2 4 5 7 10 14 20 28 35 70 140 181 362 724 905 1267 1810 2534 3620 5068 6335 9133 12670 18266 25340 36532 45665 63931 91330 127862 182660 255724 319655 639310 1278620 1653073 3306146 6612292 8265365 11571511 16530730 23143022 33061460 46286044 57857555 115715110 231430220