18133638 has 32 divisors (see below), whose sum is σ = 38716800. Its totient is φ = 5645376.

The previous prime is 18133631. The next prime is 18133649. The reversal of 18133638 is 83633181.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18133599 and 18133608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18133631) 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, 7233 + ... + 9411.

It is an arithmetic number, because the mean of its divisors is an integer number (1209900).

Almost surely, 2^18133638 is an apocalyptic number.

18133638 is an abundant number, since it is smaller than the sum of its proper divisors (20583162).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18133638 is a wasteful number, since it uses less digits than its factorization.

18133638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2276.

The product of its digits is 10368, while the sum is 33.

The square root of 18133638 is about 4258.3609522914. The cubic root of 18133638 is about 262.7211161854.

The spelling of 18133638 in words is "eighteen million, one hundred thirty-three thousand, six hundred thirty-eight".