19666668793 has 8 divisors (see below), whose sum is σ = 20398186440. Its totient is φ = 18945676800.

The previous prime is 19666668787. The next prime is 19666668803. The reversal of 19666668793 is 39786666691.

It can be written as a sum of positive squares in 4 ways, for example, as 12076251664 + 7590417129 = 109892^2 + 87123^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 19666668793 - 2¹⁷ = 19666537721 is a prime.

It is a super-2 number, since 2×19666668793² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19666668743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2627608 + ... + 2635081.

It is an arithmetic number, because the mean of its divisors is an integer number (2549773305).

Almost surely, 2^19666668793 is an apocalyptic number.

It is an amenable number.

19666668793 is a deficient number, since it is larger than the sum of its proper divisors (731517647).

19666668793 is a wasteful number, since it uses less digits than its factorization.

19666668793 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5262827.

The product of its digits is 105815808, while the sum is 67.

The spelling of 19666668793 in words is "nineteen billion, six hundred sixty-six million, six hundred sixty-eight thousand, seven hundred ninety-three".