1918549 has 2 divisors, whose sum is σ = 1918550. Its totient is φ = 1918548.

The previous prime is 1918537. The next prime is 1918571. The reversal of 1918549 is 9458191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1918225 + 324 = 1385^2 + 18^2 .

It is an emirp because it is prime and its reverse (9458191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1918549 - 2⁵ = 1918517 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1918519) 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, 959274 + 959275.

It is an arithmetic number, because the mean of its divisors is an integer number (959275).

2^1918549 is an apocalyptic number.

It is an amenable number.

1918549 is a deficient number, since it is larger than the sum of its proper divisors (1).

1918549 is an equidigital number, since it uses as much as digits as its factorization.

1918549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 37.

The square root of 1918549 is about 1385.1169625703. The cubic root of 1918549 is about 124.2579826645.

The spelling of 1918549 in words is "one million, nine hundred eighteen thousand, five hundred forty-nine".