19834579840 has 128 divisors (see below), whose sum is σ = 48739410720. Its totient is φ = 7713914880.

The previous prime is 19834579823. The next prime is 19834579861. The reversal of 19834579840 is 4897543891.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-3 number, since 3×19834579840³ (a number of 32 digits) contains 333 as substring.

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 15 ways as a sum of consecutive naturals, for example, 8841759 + ... + 8844001.

Almost surely, 2^19834579840 is an apocalyptic number.

19834579840 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 19834579840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24369705360).

19834579840 is an abundant number, since it is smaller than the sum of its proper divisors (28904830880).

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

19834579840 is a wasteful number, since it uses less digits than its factorization.

19834579840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2640 (or 2628 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 58.

The spelling of 19834579840 in words is "nineteen billion, eight hundred thirty-four million, five hundred seventy-nine thousand, eight hundred forty".