18449489557 has 4 divisors (see below), whose sum is σ = 18842031936. Its totient is φ = 18056947180.

The previous prime is 18449489549. The next prime is 18449489609. The reversal of 18449489557 is 75598494481.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18449489557 - 2³ = 18449489549 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16449489557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196271119 + ... + 196271212.

It is an arithmetic number, because the mean of its divisors is an integer number (4710507984).

Almost surely, 2^18449489557 is an apocalyptic number.

It is an amenable number.

18449489557 is a deficient number, since it is larger than the sum of its proper divisors (392542379).

18449489557 is an equidigital number, since it uses as much as digits as its factorization.

18449489557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392542378.

The product of its digits is 58060800, while the sum is 64.

The spelling of 18449489557 in words is "eighteen billion, four hundred forty-nine million, four hundred eighty-nine thousand, five hundred fifty-seven".