18840247 has 2 divisors, whose sum is σ = 18840248. Its totient is φ = 18840246.

The previous prime is 18840223. The next prime is 18840271. The reversal of 18840247 is 74204881.

It is a balanced prime because it is at equal distance from previous prime (18840223) and next prime (18840271).

It is a cyclic number.

It is not a de Polignac number, because 18840247 - 2¹¹ = 18838199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18840847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9420123 + 9420124.

It is an arithmetic number, because the mean of its divisors is an integer number (9420124).

Almost surely, 2^18840247 is an apocalyptic number.

18840247 is a deficient number, since it is larger than the sum of its proper divisors (1).

18840247 is an equidigital number, since it uses as much as digits as its factorization.

18840247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14336, while the sum is 34.

The square root of 18840247 is about 4340.5353356470. The cubic root of 18840247 is about 266.0901902694.

The spelling of 18840247 in words is "eighteen million, eight hundred forty thousand, two hundred forty-seven".