19983956647446 has 96 divisors (see below), whose sum is σ = 48992790083328. Its totient is φ = 6054687908640.

The previous prime is 19983956647439. The next prime is 19983956647471. The reversal of 19983956647446 is 64474665938991.

19983956647446 is a `hidden beast` number, since 1 + 9 + 9 + 8 + 3 + 9 + 566 + 4 + 7 + 4 + 46 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 30592720 + ... + 31239116.

It is an arithmetic number, because the mean of its divisors is an integer number (510341563368).

Almost surely, 2^{19983956647446} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19983956647446, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24496395041664).

19983956647446 is an abundant number, since it is smaller than the sum of its proper divisors (29008833435882).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19983956647446 is a wasteful number, since it uses less digits than its factorization.

19983956647446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 652208 (or 652196 counting only the distinct ones).

The product of its digits is 8465264640, while the sum is 81.

The spelling of 19983956647446 in words is "nineteen trillion, nine hundred eighty-three billion, nine hundred fifty-six million, six hundred forty-seven thousand, four hundred forty-six".