19990817616 has 320 divisors, whose sum is σ = 70024089600. Its totient is φ = 4754350080.

The previous prime is 19990817593. The next prime is 19990817699. The reversal of 19990817616 is 61671809991.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 2320485 + ... + 2329083.

It is an arithmetic number, because the mean of its divisors is an integer number (218825280).

Almost surely, 2^19990817616 is an apocalyptic number.

19990817616 is a gapful number since it is divisible by the number (16) 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 19990817616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35012044800).

19990817616 is an abundant number, since it is smaller than the sum of its proper divisors (50033271984).

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

19990817616 is a wasteful number, since it uses less digits than its factorization.

19990817616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8682 (or 8676 counting only the distinct ones).

The product of its (nonzero) digits is 1469664, while the sum is 57.

The spelling of 19990817616 in words is "nineteen billion, nine hundred ninety million, eight hundred seventeen thousand, six hundred sixteen".