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18028729 is a prime number
BaseRepresentation
bin100010011000…
…1100010111001
31020220221202201
41010301202321
514103404404
61442230201
7306145615
oct104614271
936827681
1018028729
11a1a4284
126055361
1339730b4
142574345
1518b1ca4
hex11318b9

18028729 has 2 divisors, whose sum is σ = 18028730. Its totient is φ = 18028728.

The previous prime is 18028727. The next prime is 18028753. The reversal of 18028729 is 92782081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10738729 + 7290000 = 3277^2 + 2700^2 .

It is a cyclic number.

It is not a de Polignac number, because 18028729 - 21 = 18028727 is a prime.

Together with 18028727, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18028723) 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 as a sum of consecutive naturals, namely, 9014364 + 9014365.

It is an arithmetic number, because the mean of its divisors is an integer number (9014365).

Almost surely, 218028729 is an apocalyptic number.

It is an amenable number.

18028729 is a deficient number, since it is larger than the sum of its proper divisors (1).

18028729 is an equidigital number, since it uses as much as digits as its factorization.

18028729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 18028729 is about 4246.0250823564. The cubic root of 18028729 is about 262.2134936036.

The spelling of 18028729 in words is "eighteen million, twenty-eight thousand, seven hundred twenty-nine".