18489744529 has 3 divisors (see below), whose sum is σ = 18489880507. Its totient is φ = 18489608552.

The previous prime is 18489744509. The next prime is 18489744577. The reversal of 18489744529 is 92544798481.

The square root of 18489744529 is 135977.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 16644870225 + 1844874304 = 129015^2 + 42952^2 .

It is not a de Polignac number, because 18489744529 - 2¹³ = 18489736337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18489744509) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 67989 + ... + 203965.

Almost surely, 2^18489744529 is an apocalyptic number.

18489744529 is the 135977-th square number.

18489744529 is the 67989-th centered octagonal number.

It is an amenable number.

18489744529 is a deficient number, since it is larger than the sum of its proper divisors (135978).

18489744529 is an frugal number, since it uses more digits than its factorization.

18489744529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271954 (or 135977 counting only the distinct ones).

The product of its digits is 23224320, while the sum is 61.

The spelling of 18489744529 in words is "eighteen billion, four hundred eighty-nine million, seven hundred forty-four thousand, five hundred twenty-nine".