28105992 has 48 divisors (see below), whose sum is σ = 77985180. Its totient is φ = 9139200.

The previous prime is 28105991. The next prime is 28105999. The reversal of 28105992 is 29950182.

It can be written as a sum of positive squares in 2 ways, for example, as 25462116 + 2643876 = 5046^2 + 1626^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28105991) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1809 + ... + 7712.

Almost surely, 2^28105992 is an apocalyptic number.

It is an amenable number.

28105992 is an abundant number, since it is smaller than the sum of its proper divisors (49879188).

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

28105992 is a wasteful number, since it uses less digits than its factorization.

28105992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9574 (or 9567 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 28105992 is about 5301.5084645787. The cubic root of 28105992 is about 304.0415744157.

The spelling of 28105992 in words is "twenty-eight million, one hundred five thousand, nine hundred ninety-two".