19668643973 has 16 divisors (see below), whose sum is σ = 21914193600. Its totient is φ = 17501950080.

The previous prime is 19668643963. The next prime is 19668644011. The reversal of 19668643973 is 37934686691.

It is a cyclic number.

It is not a de Polignac number, because 19668643973 - 2⁴ = 19668643957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19668643963) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86183 + ... + 216251.

It is an arithmetic number, because the mean of its divisors is an integer number (1369637100).

Almost surely, 2^19668643973 is an apocalyptic number.

It is an amenable number.

19668643973 is a deficient number, since it is larger than the sum of its proper divisors (2245549627).

19668643973 is a wasteful number, since it uses less digits than its factorization.

19668643973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130372.

The product of its digits is 35271936, while the sum is 62.

The spelling of 19668643973 in words is "nineteen billion, six hundred sixty-eight million, six hundred forty-three thousand, nine hundred seventy-three".