18638545 has 8 divisors (see below), whose sum is σ = 23682024. Its totient is φ = 14033664.

The previous prime is 18638519. The next prime is 18638573. The reversal of 18638545 is 54583681.

It can be written as a sum of positive squares in 4 ways, for example, as 5764801 + 12873744 = 2401^2 + 3588^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18638545 - 2¹⁵ = 18605777 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18638498 and 18638507.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109554 + ... + 109723.

It is an arithmetic number, because the mean of its divisors is an integer number (2960253).

Almost surely, 2^18638545 is an apocalyptic number.

It is an amenable number.

18638545 is a deficient number, since it is larger than the sum of its proper divisors (5043479).

18638545 is a wasteful number, since it uses less digits than its factorization.

18638545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219299.

The product of its digits is 115200, while the sum is 40.

The square root of 18638545 is about 4317.2381217626. The cubic root of 18638545 is about 265.1372020032.

The spelling of 18638545 in words is "eighteen million, six hundred thirty-eight thousand, five hundred forty-five".