19998689400 has 480 divisors, whose sum is σ = 74863958400. Its totient is φ = 4931539200.

The previous prime is 19998689327. The next prime is 19998689413. The reversal of 19998689400 is 498689991.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 13234645 + ... + 13236155.

It is an arithmetic number, because the mean of its divisors is an integer number (155966580).

Almost surely, 2^19998689400 is an apocalyptic number.

19998689400 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 19998689400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37431979200).

19998689400 is an abundant number, since it is smaller than the sum of its proper divisors (54865269000).

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

19998689400 is a wasteful number, since it uses less digits than its factorization.

19998689400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1601 (or 1583 counting only the distinct ones).

The product of its (nonzero) digits is 10077696, while the sum is 63.

The spelling of 19998689400 in words is "nineteen billion, nine hundred ninety-eight million, six hundred eighty-nine thousand, four hundred".