19721860063 has 2 divisors, whose sum is σ = 19721860064. Its totient is φ = 19721860062.

The previous prime is 19721860061. The next prime is 19721860069. The reversal of 19721860063 is 36006812791.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19721860063 - 2¹ = 19721860061 is a prime.

Together with 19721860061, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19721860061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9860930031 + 9860930032.

It is an arithmetic number, because the mean of its divisors is an integer number (9860930032).

Almost surely, 2^19721860063 is an apocalyptic number.

19721860063 is a deficient number, since it is larger than the sum of its proper divisors (1).

19721860063 is an equidigital number, since it uses as much as digits as its factorization.

19721860063 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 43.

The spelling of 19721860063 in words is "nineteen billion, seven hundred twenty-one million, eight hundred sixty thousand, sixty-three".