18668840249 has 16 divisors (see below), whose sum is σ = 19208164608. Its totient is φ = 18135946752.

The previous prime is 18668840231. The next prime is 18668840273. The reversal of 18668840249 is 94204886681.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18668840249 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18668840194 and 18668840203.

It is not an unprimeable number, because it can be changed into a prime (18668840209) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3763679 + ... + 3768635.

It is an arithmetic number, because the mean of its divisors is an integer number (1200510288).

Almost surely, 2^18668840249 is an apocalyptic number.

It is an amenable number.

18668840249 is a deficient number, since it is larger than the sum of its proper divisors (539324359).

18668840249 is a wasteful number, since it uses less digits than its factorization.

18668840249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5584.

The product of its (nonzero) digits is 5308416, while the sum is 56.

The spelling of 18668840249 in words is "eighteen billion, six hundred sixty-eight million, eight hundred forty thousand, two hundred forty-nine".