18439845 has 16 divisors (see below), whose sum is σ = 29782080. Its totient is φ = 9741824.

The previous prime is 18439831. The next prime is 18439847. The reversal of 18439845 is 54893481.

It is a cyclic number.

It is not a de Polignac number, because 18439845 - 2⁴ = 18439829 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18439797 and 18439806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18439847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4140 + ... + 7349.

It is an arithmetic number, because the mean of its divisors is an integer number (1861380).

Almost surely, 2^18439845 is an apocalyptic number.

18439845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18439845 is a deficient number, since it is larger than the sum of its proper divisors (11342235).

18439845 is a wasteful number, since it uses less digits than its factorization.

18439845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11604.

The product of its digits is 138240, while the sum is 42.

The square root of 18439845 is about 4294.1640630046. The cubic root of 18439845 is about 264.1916508970.

The spelling of 18439845 in words is "eighteen million, four hundred thirty-nine thousand, eight hundred forty-five".