18456838 has 4 divisors (see below), whose sum is σ = 27685260. Its totient is φ = 9228418.

The previous prime is 18456799. The next prime is 18456857. The reversal of 18456838 is 83865481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83865481 = 7 ⋅11980783.

It is a junction number, because it is equal to n+sod(n) for n = 18456794 and 18456803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4614208 + ... + 4614211.

It is an arithmetic number, because the mean of its divisors is an integer number (6921315).

Almost surely, 2^18456838 is an apocalyptic number.

18456838 is a deficient number, since it is larger than the sum of its proper divisors (9228422).

18456838 is an equidigital number, since it uses as much as digits as its factorization.

18456838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9228421.

The product of its digits is 184320, while the sum is 43.

The square root of 18456838 is about 4296.1422229717. The cubic root of 18456838 is about 264.2727801107.

The spelling of 18456838 in words is "eighteen million, four hundred fifty-six thousand, eight hundred thirty-eight".