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128316381 = 3197921613
BaseRepresentation
bin1111010010111…
…11001111011101
322221110010222120
413221133033131
5230322111011
620422133153
73115446144
oct751371735
9287403876
10128316381
1166481aa6
1236b811b9
132077936b
141308275b
15b3e9a06
hex7a5f3dd

128316381 has 8 divisors (see below), whose sum is σ = 171182880. Its totient is φ = 85497072.

The previous prime is 128316361. The next prime is 128316389. The reversal of 128316381 is 183613821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128316381 - 26 = 128316317 is a prime.

It is a super-2 number, since 2×1283163812 = 32930187265874322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128316389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4870 + ... + 16743.

It is an arithmetic number, because the mean of its divisors is an integer number (21397860).

Almost surely, 2128316381 is an apocalyptic number.

It is an amenable number.

128316381 is a deficient number, since it is larger than the sum of its proper divisors (42866499).

128316381 is a wasteful number, since it uses less digits than its factorization.

128316381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23595.

The product of its digits is 6912, while the sum is 33.

The square root of 128316381 is about 11327.6820665130. The cubic root of 128316381 is about 504.3833023636.

The spelling of 128316381 in words is "one hundred twenty-eight million, three hundred sixteen thousand, three hundred eighty-one".

Divisors: 1 3 1979 5937 21613 64839 42772127 128316381