18236749 has 2 divisors, whose sum is σ = 18236750. Its totient is φ = 18236748.

The previous prime is 18236741. The next prime is 18236753. The reversal of 18236749 is 94763281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16564900 + 1671849 = 4070^2 + 1293^2 .

It is a cyclic number.

It is not a de Polignac number, because 18236749 - 2³ = 18236741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18236741) 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, 9118374 + 9118375.

It is an arithmetic number, because the mean of its divisors is an integer number (9118375).

Almost surely, 2^18236749 is an apocalyptic number.

It is an amenable number.

18236749 is a deficient number, since it is larger than the sum of its proper divisors (1).

18236749 is an equidigital number, since it uses as much as digits as its factorization.

18236749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 40.

The square root of 18236749 is about 4270.4506787926. The cubic root of 18236749 is about 263.2181345539.

The spelling of 18236749 in words is "eighteen million, two hundred thirty-six thousand, seven hundred forty-nine".