18495403849 has 4 divisors (see below), whose sum is σ = 19918127236. Its totient is φ = 17072680464.

The previous prime is 18495403841. The next prime is 18495403867. The reversal of 18495403849 is 94830459481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94830459481 = 163259 ⋅580859.

It can be written as a sum of positive squares in 2 ways, for example, as 1220244624 + 17275159225 = 34932^2 + 131435^2 .

It is a cyclic number.

It is not a de Polignac number, because 18495403849 - 2³ = 18495403841 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18495403849.

It is not an unprimeable number, because it can be changed into a prime (18495403841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 711361674 + ... + 711361699.

It is an arithmetic number, because the mean of its divisors is an integer number (4979531809).

Almost surely, 2^18495403849 is an apocalyptic number.

It is an amenable number.

18495403849 is a deficient number, since it is larger than the sum of its proper divisors (1422723387).

18495403849 is a wasteful number, since it uses less digits than its factorization.

18495403849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1422723386.

The product of its (nonzero) digits is 4976640, while the sum is 55.

The spelling of 18495403849 in words is "eighteen billion, four hundred ninety-five million, four hundred three thousand, eight hundred forty-nine".