Have you tried Math::BigInt or Math::BigFloat? It does work with numbers with thousands of digits.

use Math::BigFloat ();

$x = Math::BigFloat->new("15000000") / 222;
print("$x\n");
# 67567.56756756756756756756756756756756757

$x = Math::BigFloat->new("67567.57") * 222;
print("$x\n");
# 15000000.54
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