28199840 has 96 divisors (see below), whose sum is σ = 71124480. Its totient is φ = 10543104.

The previous prime is 28199837. The next prime is 28199879. The reversal of 28199840 is 4899182.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 290672 + ... + 290768.

It is an arithmetic number, because the mean of its divisors is an integer number (740880).

Almost surely, 2^28199840 is an apocalyptic number.

28199840 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 28199840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35562240).

28199840 is an abundant number, since it is smaller than the sum of its proper divisors (42924640).

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

28199840 is a wasteful number, since it uses less digits than its factorization.

28199840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 28199840 is about 5310.3521540478. The cubic root of 28199840 is about 304.3796042772.

The spelling of 28199840 in words is "twenty-eight million, one hundred ninety-nine thousand, eight hundred forty".