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128442720 = 25357243127
BaseRepresentation
bin1111010011111…
…10000101100000
322221200120021210
413221332011200
5230340131340
620424550120
73116513400
oct751760540
9287616253
10128442720
1166558a0a
1237022340
13207c1a13
14130b6800
15b422180
hex7a7e160

128442720 has 288 divisors, whose sum is σ = 485388288. Its totient is φ = 28449792.

The previous prime is 128442659. The next prime is 128442731. The reversal of 128442720 is 27244821.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1011297 + ... + 1011423.

It is an arithmetic number, because the mean of its divisors is an integer number (1685376).

Almost surely, 2128442720 is an apocalyptic number.

128442720 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 128442720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242694144).

128442720 is an abundant number, since it is smaller than the sum of its proper divisors (356945568).

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

128442720 is a wasteful number, since it uses less digits than its factorization.

128442720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 30.

The square root of 128442720 is about 11333.2572546466. The cubic root of 128442720 is about 504.5487849497.

The spelling of 128442720 in words is "one hundred twenty-eight million, four hundred forty-two thousand, seven hundred twenty".