18697728 has 160 divisors (see below), whose sum is σ = 59710464. Its totient is φ = 5087232.

The previous prime is 18697727. The next prime is 18697741. The reversal of 18697728 is 82779681.

It is a Harshad number since it is a multiple of its sum of digits (48).

Its product of digits (338688) is a multiple of the sum of its prime divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18697727) 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, 397801 + ... + 397847.

Almost surely, 2^18697728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18697728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29855232).

18697728 is an abundant number, since it is smaller than the sum of its proper divisors (41012736).

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

18697728 is an equidigital number, since it uses as much as digits as its factorization.

18697728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112 (or 96 counting only the distinct ones).

The product of its digits is 338688, while the sum is 48.

The square root of 18697728 is about 4324.0869556474. The cubic root of 18697728 is about 265.4175356832.

The spelling of 18697728 in words is "eighteen million, six hundred ninety-seven thousand, seven hundred twenty-eight".