19489509812 has 6 divisors (see below), whose sum is σ = 34106642178. Its totient is φ = 9744754904.

The previous prime is 19489509811. The next prime is 19489509817. The reversal of 19489509812 is 21890598491.

It can be written as a sum of positive squares in only one way, i.e., 9968824336 + 9520685476 = 99844^2 + 97574^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19489509811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2436188723 + ... + 2436188730.

It is an arithmetic number, because the mean of its divisors is an integer number (5684440363).

Almost surely, 2^19489509812 is an apocalyptic number.

It is an amenable number.

19489509812 is a deficient number, since it is larger than the sum of its proper divisors (14617132366).

19489509812 is a wasteful number, since it uses less digits than its factorization.

19489509812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4872377457 (or 4872377455 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 56.

The spelling of 19489509812 in words is "nineteen billion, four hundred eighty-nine million, five hundred nine thousand, eight hundred twelve".