19890812 has 12 divisors (see below), whose sum is σ = 34866216. Its totient is φ = 9929040.

The previous prime is 19890797. The next prime is 19890817. The reversal of 19890812 is 21809891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19890817) 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, 1118 + ... + 6405.

It is an arithmetic number, because the mean of its divisors is an integer number (2905518).

Almost surely, 2^19890812 is an apocalyptic number.

It is an amenable number.

19890812 is a deficient number, since it is larger than the sum of its proper divisors (14975404).

19890812 is a wasteful number, since it uses less digits than its factorization.

19890812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8188 (or 8186 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 38.

The square root of 19890812 is about 4459.9116583179. The cubic root of 19890812 is about 270.9468902791.

It can be divided in two parts, 19890 and 812, that added together give a palindrome (20702).

The spelling of 19890812 in words is "nineteen million, eight hundred ninety thousand, eight hundred twelve".