19749801600 has 432 divisors, whose sum is σ = 72050391270. Its totient is φ = 5151068160.

The previous prime is 19749801581. The next prime is 19749801613. The reversal of 19749801600 is 610894791.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 18865571904 + 884229696 = 137352^2 + 29736^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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 53 ways as a sum of consecutive naturals, for example, 100252702 + ... + 100252898.

Almost surely, 2^19749801600 is an apocalyptic number.

19749801600 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 19749801600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36025195635).

19749801600 is an abundant number, since it is smaller than the sum of its proper divisors (52300589670).

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

19749801600 is a wasteful number, since it uses less digits than its factorization.

19749801600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345 (or 266 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The spelling of 19749801600 in words is "nineteen billion, seven hundred forty-nine million, eight hundred one thousand, six hundred".