28198840 has 32 divisors (see below), whose sum is σ = 65496960. Its totient is φ = 10915200.

The previous prime is 28198829. The next prime is 28198843. The reversal of 28198840 is 4889182.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 28198793 and 28198802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28198843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10131 + ... + 12610.

It is an arithmetic number, because the mean of its divisors is an integer number (2046780).

Almost surely, 2^28198840 is an apocalyptic number.

28198840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28198840 is an abundant number, since it is smaller than the sum of its proper divisors (37298120).

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

28198840 is a wasteful number, since it uses less digits than its factorization.

28198840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22783 (or 22779 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 28198840 is about 5310.2579974988. The cubic root of 28198840 is about 304.3760063466.

The spelling of 28198840 in words is "twenty-eight million, one hundred ninety-eight thousand, eight hundred forty".