19963247981 has 8 divisors (see below), whose sum is σ = 20095193880. Its totient is φ = 19831492672.

The previous prime is 19963247933. The next prime is 19963248031. The reversal of 19963247981 is 18974236991.

It can be written as a sum of positive squares in 4 ways, for example, as 7887216100 + 12076031881 = 88810^2 + 109891^2 .

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 19963247981 - 2¹⁸ = 19962985837 is a prime.

It is a super-2 number, since 2×19963247981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 19963247981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19963247081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 165671 + ... + 259563.

It is an arithmetic number, because the mean of its divisors is an integer number (2511899235).

Almost surely, 2^19963247981 is an apocalyptic number.

It is an amenable number.

19963247981 is a deficient number, since it is larger than the sum of its proper divisors (131945899).

19963247981 is a wasteful number, since it uses less digits than its factorization.

19963247981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95295.

The product of its digits is 5878656, while the sum is 59.

The spelling of 19963247981 in words is "nineteen billion, nine hundred sixty-three million, two hundred forty-seven thousand, nine hundred eighty-one".