((#expr: ((worldpop-base)) + ((worldpop-daily-inc)) * (((Age in days|2021|7|1)) + (((#time:U)) mod 86400) / 86400) round -3))

Formatted with commas – ((formatnum:((worldpop)) )) → 8,094,290,000
Present value of ((worldpop-base)) → 8,045,311,448
Present value of ((worldpop-daily-inc)) → 192,214.4
Updates every 1,000 increase in population
Formatted to nearest 1,000 to reduce likelihood of display in scientific notation, and also to avoid false precision
((#expr: ((worldpop))/1000000000 round 2)) billion today → 8.09 billion today

Regarding rounding

if rounded to nearest 100-thousand, will often display in scientific notation
if round ends in 5 zeroes, there is an intermittent sci notation problem
This CAN happen even if the number is rounded to 0 places - IF the number ends in 5 zeroes
results are inconsistent, seemingly dependent on which server renders the numbers

Places rounded to	result	"textified"
none	8,374,959,144
0	8,374,959,144
1	8,374,959,140	8374959140
2	8,374,959,100	8374959100
3	8,374,959,000	8374959000
4	8,374,960,000	8374960000
5	8,375,000,000	8375000000
6	8,375,000,000	8375000000
7	8,370,000,000	8370000000
8	8,400,000,000	8400000000
9	8,000,000,000	8000000000

Data source

"Demographic Indicators Compact". World Population Prospects, the 2022 Revision. United Nations Department of Economic and Social Affairs, Population Division, Population Estimates and Projections Section. July 2022.