19999999966 has 8 divisors (see below), whose sum is σ = 30009572640. Its totient is φ = 9996809088.

The previous prime is 19999999939. The next prime is 19999999967. The reversal of 19999999966 is 66999999991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19999999967) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1587606 + ... + 1600153.

It is an arithmetic number, because the mean of its divisors is an integer number (3751196580).

Almost surely, 2^19999999966 is an apocalyptic number.

19999999966 is a deficient number, since it is larger than the sum of its proper divisors (10009572674).

19999999966 is a wasteful number, since it uses less digits than its factorization.

19999999966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3190898.

The product of its digits is 1549681956, while the sum is 85.

It can be divided in two parts, 1999999996 and 6, that added together give a palindrome (2000000002).

The spelling of 19999999966 in words is "nineteen billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred sixty-six".