Ключевые слова: age milestone, alphabetical position th, angel number, anniversary, atomic mass, atomic number of calcium, base number, binary code, binary representation, birthdate, chemical symbol ca, composite number, counting number, cube of, divisible by, double digit, even number, group element, hexadecimal representation, integer, lucky number, milestone birthday, multiple of, multiple of and, natural number, number between and, numerology, ordinal number, perfect number, positive number, prime factorization , product of and, roman numeral xx, score of, significant number, squared number, sum of and, twentyyearold,