28198404 has 72 divisors (see below), whose sum is σ = 77739480. Its totient is φ = 8566272.

The previous prime is 28198381. The next prime is 28198421. The reversal of 28198404 is 40489182.

It can be written as a sum of positive squares in 4 ways, for example, as 3992004 + 24206400 = 1998^2 + 4920^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 41314 + ... + 41990.

It is an arithmetic number, because the mean of its divisors is an integer number (1079715).

Almost surely, 2^28198404 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 28198404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38869740).

28198404 is an abundant number, since it is smaller than the sum of its proper divisors (49541076).

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

28198404 is a wasteful number, since it uses less digits than its factorization.

28198404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 789 (or 784 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 28198404 is about 5310.2169447208. The cubic root of 28198404 is about 304.3744376222.

The spelling of 28198404 in words is "twenty-eight million, one hundred ninety-eight thousand, four hundred four".