19663897563 has 24 divisors (see below), whose sum is σ = 30116595600. Its totient is φ = 12328637184.

The previous prime is 19663897529. The next prime is 19663897573. The reversal of 19663897563 is 36579836691.

19663897563 is a `hidden beast` number, since 1 + 9 + 6 + 63 + 8 + 9 + 7 + 563 = 666.

It is not a de Polignac number, because 19663897563 - 2⁸ = 19663897307 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19663897563.

It is not an unprimeable number, because it can be changed into a prime (19663897573) 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 23 ways as a sum of consecutive naturals, for example, 396258 + ... + 443111.

It is an arithmetic number, because the mean of its divisors is an integer number (1254858150).

Almost surely, 2^19663897563 is an apocalyptic number.

19663897563 is a deficient number, since it is larger than the sum of its proper divisors (10452698037).

19663897563 is a wasteful number, since it uses less digits than its factorization.

19663897563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 839531 (or 839528 counting only the distinct ones).

The product of its digits is 44089920, while the sum is 63.

The spelling of 19663897563 in words is "nineteen billion, six hundred sixty-three million, eight hundred ninety-seven thousand, five hundred sixty-three".