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128920080 = 24352918523
BaseRepresentation
bin1111010111100…
…10101000010000
322222120211002210
413223302220100
5231000420310
620443112120
73123542202
oct753625020
9288524083
10128920080
1166854623
1237212640
132092b093
141319c772
15b4b8820
hex7af2a10

128920080 has 80 divisors (see below), whose sum is σ = 413455680. Its totient is φ = 33191424.

The previous prime is 128920067. The next prime is 128920087. The reversal of 128920080 is 80029821.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (128920087) 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 15 ways as a sum of consecutive naturals, for example, 2302 + ... + 16221.

It is an arithmetic number, because the mean of its divisors is an integer number (5168196).

Almost surely, 2128920080 is an apocalyptic number.

128920080 is a gapful number since it is divisible by the number (10) 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 128920080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (206727840).

128920080 is an abundant number, since it is smaller than the sum of its proper divisors (284535600).

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

128920080 is a wasteful number, since it uses less digits than its factorization.

128920080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18568 (or 18562 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 128920080 is about 11354.2978646854. The cubic root of 128920080 is about 505.1730674993.

The spelling of 128920080 in words is "one hundred twenty-eight million, nine hundred twenty thousand, eighty".

Divisors: 1 2 3 4 5 6 8 10 12 15 16 20 24 29 30 40 48 58 60 80 87 116 120 145 174 232 240 290 348 435 464 580 696 870 1160 1392 1740 2320 3480 6960 18523 37046 55569 74092 92615 111138 148184 185230 222276 277845 296368 370460 444552 537167 555690 740920 889104 1074334 1111380 1481840 1611501 2148668 2222760 2685835 3223002 4297336 4445520 5371670 6446004 8057505 8594672 10743340 12892008 16115010 21486680 25784016 32230020 42973360 64460040 128920080