28275840 has 96 divisors (see below), whose sum is σ = 97659900. Its totient is φ = 7538688.

The previous prime is 28275839. The next prime is 28275853. The reversal of 28275840 is 4857282.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 26132544 + 2143296 = 5112^2 + 1464^2 .

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 = 28275795 and 28275804.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3306 + ... + 8214.

Almost surely, 2^28275840 is an apocalyptic number.

28275840 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 28275840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48829950).

28275840 is an abundant number, since it is smaller than the sum of its proper divisors (69384060).

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

28275840 is a wasteful number, since it uses less digits than its factorization.

28275840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4934 (or 4919 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The square root of 28275840 is about 5317.5031734828. The cubic root of 28275840 is about 304.6527984937.

The spelling of 28275840 in words is "twenty-eight million, two hundred seventy-five thousand, eight hundred forty".