18723834 has 48 divisors (see below), whose sum is σ = 43984512. Its totient is φ = 5733504.

The previous prime is 18723833. The next prime is 18723871. The reversal of 18723834 is 43832781.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18723833) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12447 + ... + 13869.

It is an arithmetic number, because the mean of its divisors is an integer number (916344).

Almost surely, 2^18723834 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18723834, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21992256).

18723834 is an abundant number, since it is smaller than the sum of its proper divisors (25260678).

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

18723834 is a wasteful number, since it uses less digits than its factorization.

18723834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1491 (or 1488 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 18723834 is about 4327.1045746550. The cubic root of 18723834 is about 265.5410046577.

The spelling of 18723834 in words is "eighteen million, seven hundred twenty-three thousand, eight hundred thirty-four".