19749075840 has 384 divisors, whose sum is σ = 74226297600. Its totient is φ = 4809424896.

The previous prime is 19749075823. The next prime is 19749075887. The reversal of 19749075840 is 4857094791.

19749075840 is a `hidden beast` number, since 1 + 9 + 7 + 490 + 75 + 84 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7262001 + ... + 7264719.

It is an arithmetic number, because the mean of its divisors is an integer number (193297650).

Almost surely, 2^19749075840 is an apocalyptic number.

19749075840 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 19749075840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37113148800).

19749075840 is an abundant number, since it is smaller than the sum of its proper divisors (54477221760).

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

19749075840 is a wasteful number, since it uses less digits than its factorization.

19749075840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2854 (or 2839 counting only the distinct ones).

The product of its (nonzero) digits is 2540160, while the sum is 54.

The spelling of 19749075840 in words is "nineteen billion, seven hundred forty-nine million, seventy-five thousand, eight hundred forty".