18421349 has 2 divisors, whose sum is σ = 18421350. Its totient is φ = 18421348.

The previous prime is 18421343. The next prime is 18421357. The reversal of 18421349 is 94312481.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17698849 + 722500 = 4207^2 + 850^2 .

It is a cyclic number.

It is not a de Polignac number, because 18421349 - 2⁸ = 18421093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18421343) 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, 9210674 + 9210675.

It is an arithmetic number, because the mean of its divisors is an integer number (9210675).

Almost surely, 2^18421349 is an apocalyptic number.

It is an amenable number.

18421349 is a deficient number, since it is larger than the sum of its proper divisors (1).

18421349 is an equidigital number, since it uses as much as digits as its factorization.

18421349 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 32.

The square root of 18421349 is about 4292.0099021321. The cubic root of 18421349 is about 264.1032892816.

The spelling of 18421349 in words is "eighteen million, four hundred twenty-one thousand, three hundred forty-nine".