18023634 has 40 divisors (see below), whose sum is σ = 40981248. Its totient is φ = 5919480.

The previous prime is 18023633. The next prime is 18023639. The reversal of 18023634 is 43632081.

It is a happy number.

18023634 is a `hidden beast` number, since 1 + 8 + 0 + 23 + 634 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 18023598 and 18023607.

It is not an unprimeable number, because it can be changed into a prime (18023633) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10719 + ... + 12285.

Almost surely, 2^18023634 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18023634, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20490624).

18023634 is an abundant number, since it is smaller than the sum of its proper divisors (22957614).

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

18023634 is a wasteful number, since it uses less digits than its factorization.

18023634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1652 (or 1643 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 18023634 is about 4245.4250670575. The cubic root of 18023634 is about 262.1887903716.

The spelling of 18023634 in words is "eighteen million, twenty-three thousand, six hundred thirty-four".