28511240 has 16 divisors (see below), whose sum is σ = 64150380. Its totient is φ = 11404480.

The previous prime is 28511221. The next prime is 28511251. The reversal of 28511240 is 4211582.

It can be written as a sum of positive squares in 2 ways, for example, as 28153636 + 357604 = 5306^2 + 598^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 356351 + ... + 356430.

Almost surely, 2^28511240 is an apocalyptic number.

28511240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28511240 is an abundant number, since it is smaller than the sum of its proper divisors (35639140).

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

28511240 is a wasteful number, since it uses less digits than its factorization.

28511240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 712792 (or 712788 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 28511240 is about 5339.5917446936. The cubic root of 28511240 is about 305.4958877552.

The spelling of 28511240 in words is "twenty-eight million, five hundred eleven thousand, two hundred forty".