19973423808 has 672 divisors, whose sum is σ = 69231052800. Its totient is φ = 5448425472.

The previous prime is 19973423803. The next prime is 19973423849. The reversal of 19973423808 is 80832437991.

19973423808 is a `hidden beast` number, since 199 + 73 + 4 + 2 + 380 + 8 = 666.

It is a super-2 number, since 2×19973423808² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19973423803) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 193916685 + ... + 193916787.

It is an arithmetic number, because the mean of its divisors is an integer number (103022400).

Almost surely, 2^19973423808 is an apocalyptic number.

19973423808 is a gapful number since it is divisible by the number (18) 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 19973423808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34615526400).

19973423808 is an abundant number, since it is smaller than the sum of its proper divisors (49257628992).

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

19973423808 is a wasteful number, since it uses less digits than its factorization.

19973423808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 19973423808 in words is "nineteen billion, nine hundred seventy-three million, four hundred twenty-three thousand, eight hundred eight".