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28928680 = 23511243139
BaseRepresentation
bin110111001011…
…0101010101000
32000102201200121
41232112222220
524401204210
62512013024
7500614114
oct156265250
960381617
1028928680
1115369600
129831174
135cbb481
143bb0744
1528166da
hex1b96aa8

28928680 has 96 divisors (see below), whose sum is σ = 73735200. Its totient is φ = 10200960.

The previous prime is 28928677. The next prime is 28928681. The reversal of 28928680 is 8682982.

28928680 = T144 + T145 + ... + T560.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is not an unprimeable number, because it can be changed into a prime (28928681) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 208051 + ... + 208189.

It is an arithmetic number, because the mean of its divisors is an integer number (768075).

Almost surely, 228928680 is an apocalyptic number.

28928680 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 28928680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36867600).

28928680 is an abundant number, since it is smaller than the sum of its proper divisors (44806520).

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

28928680 is a wasteful number, since it uses less digits than its factorization.

28928680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215 (or 200 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 43.

The square root of 28928680 is about 5378.5388350369. The cubic root of 28928680 is about 306.9796164675.

The spelling of 28928680 in words is "twenty-eight million, nine hundred twenty-eight thousand, six hundred eighty".

Divisors: 1 2 4 5 8 10 11 20 22 40 43 44 55 86 88 110 121 139 172 215 220 242 278 344 430 440 473 484 556 605 695 860 946 968 1112 1210 1390 1529 1720 1892 2365 2420 2780 3058 3784 4730 4840 5203 5560 5977 6116 7645 9460 10406 11954 12232 15290 16819 18920 20812 23908 26015 29885 30580 33638 41624 47816 52030 59770 61160 65747 67276 84095 104060 119540 131494 134552 168190 208120 239080 262988 328735 336380 525976 657470 672760 723217 1314940 1446434 2629880 2892868 3616085 5785736 7232170 14464340 28928680