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31000243 is a prime number
BaseRepresentation
bin111011001000…
…0011010110011
32011022222100011
41312100122303
530414001433
63024235351
7524332501
oct166203263
964288304
1031000243
1116553a3a
12a46bb57
136565351
14418d671
152ac53cd
hex1d906b3

31000243 has 2 divisors, whose sum is σ = 31000244. Its totient is φ = 31000242.

The previous prime is 31000241. The next prime is 31000259. The reversal of 31000243 is 34200013.

It is a weak prime.

It is an emirp because it is prime and its reverse (34200013) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31000243 - 21 = 31000241 is a prime.

It is a super-2 number, since 2×310002432 = 1922030132118098, which contains 22 as substring.

Together with 31000241, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31000241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15500121 + 15500122.

It is an arithmetic number, because the mean of its divisors is an integer number (15500122).

Almost surely, 231000243 is an apocalyptic number.

31000243 is a deficient number, since it is larger than the sum of its proper divisors (1).

31000243 is an equidigital number, since it uses as much as digits as its factorization.

31000243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 31000243 is about 5567.7861848315. The cubic root of 31000243 is about 314.1388860494.

Adding to 31000243 its reverse (34200013), we get a palindrome (65200256).

The spelling of 31000243 in words is "thirty-one million, two hundred forty-three", and thus it is an aban number.