18404449569 has 27 divisors (see below), whose sum is σ = 29227764657. Its totient is φ = 11151498600.

The previous prime is 18404449537. The next prime is 18404449571. The reversal of 18404449569 is 96594440481.

The square root of 18404449569 is 135663.

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

18404449569 is a `hidden beast` number, since 18 + 40 + 44 + 495 + 69 = 666.

It is not a de Polignac number, because 18404449569 - 2⁵ = 18404449537 is a prime.

It is a super-2 number, since 2×18404449569² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18404449669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4474824 + ... + 4478934.

Almost surely, 2^18404449569 is an apocalyptic number.

18404449569 is the 135663-rd square number.

18404449569 is the 67832-nd centered octagonal number.

It is an amenable number.

18404449569 is a deficient number, since it is larger than the sum of its proper divisors (10823315088).

18404449569 is an frugal number, since it uses more digits than its factorization.

18404449569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8250 (or 4125 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 18404449569 in words is "eighteen billion, four hundred four million, four hundred forty-nine thousand, five hundred sixty-nine".