28105580 has 24 divisors (see below), whose sum is σ = 59370192. Its totient is φ = 11175872.

The previous prime is 28105559. The next prime is 28105589. The reversal of 28105580 is 8550182.

It is a super-3 number, since 3×28105580³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (28105589) 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, 602 + ... + 7521.

It is an arithmetic number, because the mean of its divisors is an integer number (2473758).

Almost surely, 2^28105580 is an apocalyptic number.

28105580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28105580 is an abundant number, since it is smaller than the sum of its proper divisors (31264612).

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

28105580 is a wasteful number, since it uses less digits than its factorization.

28105580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8305 (or 8303 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 29.

The square root of 28105580 is about 5301.4696075711. The cubic root of 28105580 is about 304.0400887806.

The spelling of 28105580 in words is "twenty-eight million, one hundred five thousand, five hundred eighty".