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78873281 is a prime number
BaseRepresentation
bin1001011001110…
…00001011000001
312111102011210122
410230320023001
5130142421111
611454310025
71645261154
oct454701301
9174364718
1078873281
1140581733
12224b8315
13134575a6
14a691c9b
156dcecdb
hex4b382c1

78873281 has 2 divisors, whose sum is σ = 78873282. Its totient is φ = 78873280.

The previous prime is 78873247. The next prime is 78873329. The reversal of 78873281 is 18237887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57896881 + 20976400 = 7609^2 + 4580^2 .

It is an emirp because it is prime and its reverse (18237887) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-78873281 is a prime.

It is a super-2 number, since 2×788732812 = 12441988911409922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78873211) 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, 39436640 + 39436641.

It is an arithmetic number, because the mean of its divisors is an integer number (39436641).

Almost surely, 278873281 is an apocalyptic number.

It is an amenable number.

78873281 is a deficient number, since it is larger than the sum of its proper divisors (1).

78873281 is an equidigital number, since it uses as much as digits as its factorization.

78873281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 150528, while the sum is 44.

The square root of 78873281 is about 8881.0630557383. The cubic root of 78873281 is about 428.8544975595.

The spelling of 78873281 in words is "seventy-eight million, eight hundred seventy-three thousand, two hundred eighty-one".