18920249 has 2 divisors, whose sum is σ = 18920250. Its totient is φ = 18920248.

The previous prime is 18920233. The next prime is 18920281. The reversal of 18920249 is 94202981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15523600 + 3396649 = 3940^2 + 1843^2 .

It is a cyclic number.

It is not a de Polignac number, because 18920249 - 2⁴ = 18920233 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18920449) 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, 9460124 + 9460125.

It is an arithmetic number, because the mean of its divisors is an integer number (9460125).

Almost surely, 2^18920249 is an apocalyptic number.

It is an amenable number.

18920249 is a deficient number, since it is larger than the sum of its proper divisors (1).

18920249 is an equidigital number, since it uses as much as digits as its factorization.

18920249 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 18920249 is about 4349.7412566726. The cubic root of 18920249 is about 266.4662944441.

The spelling of 18920249 in words is "eighteen million, nine hundred twenty thousand, two hundred forty-nine".