19106809405 has 16 divisors (see below), whose sum is σ = 24417234864. Its totient is φ = 14303134720.

The previous prime is 19106809399. The next prime is 19106809429. The reversal of 19106809405 is 50490860191.

It can be written as a sum of positive squares in 8 ways, for example, as 3976036 + 19102833369 = 1994^2 + 138213^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19106809405 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 634966 + ... + 664375.

It is an arithmetic number, because the mean of its divisors is an integer number (1526077179).

Almost surely, 2^19106809405 is an apocalyptic number.

It is an amenable number.

19106809405 is a deficient number, since it is larger than the sum of its proper divisors (5310425459).

19106809405 is a wasteful number, since it uses less digits than its factorization.

19106809405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1299536.

The product of its (nonzero) digits is 77760, while the sum is 43.

The spelling of 19106809405 in words is "nineteen billion, one hundred six million, eight hundred nine thousand, four hundred five".