28018900 has 72 divisors (see below), whose sum is σ = 74856320. Its totient is φ = 8864640.

The previous prime is 28018897. The next prime is 28018919. The reversal of 28018900 is 981082.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7561 + ... + 10639.

Almost surely, 2^28018900 is an apocalyptic number.

28018900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28018900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37428160).

28018900 is an abundant number, since it is smaller than the sum of its proper divisors (46837420).

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

28018900 is a wasteful number, since it uses less digits than its factorization.

28018900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3113 (or 3106 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 28018900 is about 5293.2882029982. The cubic root of 28018900 is about 303.7272050725.

Adding to 28018900 its reverse (981082), we get a palindrome (28999982).

The spelling of 28018900 in words is "twenty-eight million, eighteen thousand, nine hundred".