28671840 has 96 divisors (see below), whose sum is σ = 100366560. Its totient is φ = 7644672.

The previous prime is 28671821. The next prime is 28671847. The reversal of 28671840 is 4817682.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is a junction number, because it is equal to n+sod(n) for n = 28671795 and 28671804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28671847) 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, 1002 + ... + 7638.

It is an arithmetic number, because the mean of its divisors is an integer number (1045485).

Almost surely, 2^28671840 is an apocalyptic number.

28671840 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 28671840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50183280).

28671840 is an abundant number, since it is smaller than the sum of its proper divisors (71694720).

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

28671840 is a wasteful number, since it uses less digits than its factorization.

28671840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6661 (or 6647 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 28671840 is about 5354.6092294396. The cubic root of 28671840 is about 306.0684199178.

The spelling of 28671840 in words is "twenty-eight million, six hundred seventy-one thousand, eight hundred forty".