19844438680 has 64 divisors (see below), whose sum is σ = 48842196480. Its totient is φ = 7196438400.

The previous prime is 19844438671. The next prime is 19844438693. The reversal of 19844438680 is 8683444891.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100035 + ... + 222925.

It is an arithmetic number, because the mean of its divisors is an integer number (763159320).

Almost surely, 2^19844438680 is an apocalyptic number.

19844438680 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 19844438680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24421098240).

19844438680 is an abundant number, since it is smaller than the sum of its proper divisors (28997757800).

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

19844438680 is a wasteful number, since it uses less digits than its factorization.

19844438680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123280 (or 123276 counting only the distinct ones).

The product of its (nonzero) digits is 5308416, while the sum is 55.

It can be divided in two parts, 198 and 44438680, that added together give a triangular number (44438878 = T₉₄₂₇).

The spelling of 19844438680 in words is "nineteen billion, eight hundred forty-four million, four hundred thirty-eight thousand, six hundred eighty".