18129847 has 2 divisors, whose sum is σ = 18129848. Its totient is φ = 18129846.

The previous prime is 18129791. The next prime is 18129851. The reversal of 18129847 is 74892181.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18129847 - 2⁷ = 18129719 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18199847) 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, 9064923 + 9064924.

It is an arithmetic number, because the mean of its divisors is an integer number (9064924).

Almost surely, 2^18129847 is an apocalyptic number.

18129847 is a deficient number, since it is larger than the sum of its proper divisors (1).

18129847 is an equidigital number, since it uses as much as digits as its factorization.

18129847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 18129847 is about 4257.9158047101. The cubic root of 18129847 is about 262.7028068392.

The spelling of 18129847 in words is "eighteen million, one hundred twenty-nine thousand, eight hundred forty-seven".