19491812 has 12 divisors (see below), whose sum is σ = 34360620. Its totient is φ = 9674496.

The previous prime is 19491811. The next prime is 19491817. The reversal of 19491812 is 21819491.

It can be written as a sum of positive squares in 2 ways, for example, as 16128256 + 3363556 = 4016^2 + 1834^2 .

It is not an unprimeable number, because it can be changed into a prime (19491811) 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 in 3 ways as a sum of consecutive naturals, for example, 17237 + ... + 18332.

It is an arithmetic number, because the mean of its divisors is an integer number (2863385).

Almost surely, 2^19491812 is an apocalyptic number.

It is an amenable number.

19491812 is a deficient number, since it is larger than the sum of its proper divisors (14868808).

19491812 is a wasteful number, since it uses less digits than its factorization.

19491812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35710 (or 35708 counting only the distinct ones).

The product of its digits is 5184, while the sum is 35.

The square root of 19491812 is about 4414.9532273853. The cubic root of 19491812 is about 269.1229520439.

The spelling of 19491812 in words is "nineteen million, four hundred ninety-one thousand, eight hundred twelve".