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87128069 = 761204047
BaseRepresentation
bin1010011000101…
…11100000000101
320001221120020112
411030113200011
5134301044234
612351242405
72105401460
oct514274005
9201846215
1087128069
11451aa676
1225219405
1315087992
14b8002d7
1579b0ace
hex5317805

87128069 has 8 divisors (see below), whose sum is σ = 101207808. Its totient is φ = 73456560.

The previous prime is 87128051. The next prime is 87128089. The reversal of 87128069 is 96082178.

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

It is a cyclic number.

It is not a de Polignac number, because 87128069 - 212 = 87123973 is a prime.

It is a super-2 number, since 2×871280692 = 15182600815337522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87128029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101597 + ... + 102450.

It is an arithmetic number, because the mean of its divisors is an integer number (12650976).

Almost surely, 287128069 is an apocalyptic number.

It is an amenable number.

87128069 is a deficient number, since it is larger than the sum of its proper divisors (14079739).

87128069 is a wasteful number, since it uses less digits than its factorization.

87128069 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204115.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 87128069 is about 9334.2417474587. The cubic root of 87128069 is about 443.3220807943.

The spelling of 87128069 in words is "eighty-seven million, one hundred twenty-eight thousand, sixty-nine".

Divisors: 1 7 61 427 204047 1428329 12446867 87128069