19953991680 has 360 divisors, whose sum is σ = 74320274448. Its totient is φ = 4558159872.

The previous prime is 19953991679. The next prime is 19953991693. The reversal of 19953991680 is 8619935991.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12041412 + ... + 12043068.

Almost surely, 2^19953991680 is an apocalyptic number.

19953991680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19953991680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37160137224).

19953991680 is an abundant number, since it is smaller than the sum of its proper divisors (54366282768).

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

19953991680 is an equidigital number, since it uses as much as digits as its factorization.

19953991680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1707 (or 1674 counting only the distinct ones).

The product of its (nonzero) digits is 4723920, while the sum is 60.

The spelling of 19953991680 in words is "nineteen billion, nine hundred fifty-three million, nine hundred ninety-one thousand, six hundred eighty".