28139460 has 48 divisors (see below), whose sum is σ = 80136000. Its totient is φ = 7375744.

The previous prime is 28139459. The next prime is 28139467. The reversal of 28139460 is 6493182.

It is not an unprimeable number, because it can be changed into a prime (28139467) 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, 435 + ... + 7514.

It is an arithmetic number, because the mean of its divisors is an integer number (1669500).

Almost surely, 2^28139460 is an apocalyptic number.

28139460 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 28139460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40068000).

28139460 is an abundant number, since it is smaller than the sum of its proper divisors (51996540).

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

28139460 is a wasteful number, since it uses less digits than its factorization.

28139460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8020 (or 8018 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 28139460 is about 5304.6639855885. The cubic root of 28139460 is about 304.1622085625.

The spelling of 28139460 in words is "twenty-eight million, one hundred thirty-nine thousand, four hundred sixty".