18729858 has 64 divisors (see below), whose sum is σ = 46080000. Its totient is φ = 5059152.

The previous prime is 18729857. The next prime is 18729883. The reversal of 18729858 is 85892781.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18729857) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38863 + ... + 39341.

It is an arithmetic number, because the mean of its divisors is an integer number (720000).

Almost surely, 2^18729858 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18729858, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23040000).

18729858 is an abundant number, since it is smaller than the sum of its proper divisors (27350142).

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

18729858 is a wasteful number, since it uses less digits than its factorization.

18729858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 524 (or 510 counting only the distinct ones).

The product of its digits is 322560, while the sum is 48.

The square root of 18729858 is about 4327.8005961458. The cubic root of 18729858 is about 265.5694790163.

The spelling of 18729858 in words is "eighteen million, seven hundred twenty-nine thousand, eight hundred fifty-eight".