28112521 has 8 divisors (see below), whose sum is σ = 28980288. Its totient is φ = 27258000.

The previous prime is 28112507. The next prime is 28112551. The reversal of 28112521 is 12521182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28112521 - 2⁷ = 28112393 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28112492 and 28112501.

It is not an unprimeable number, because it can be changed into a prime (28112551) 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, 1086 + ... + 7576.

It is an arithmetic number, because the mean of its divisors is an integer number (3622536).

Almost surely, 2^28112521 is an apocalyptic number.

It is an amenable number.

28112521 is a deficient number, since it is larger than the sum of its proper divisors (867767).

28112521 is an equidigital number, since it uses as much as digits as its factorization.

28112521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6623.

The product of its digits is 320, while the sum is 22.

The square root of 28112521 is about 5302.1241969611. The cubic root of 28112521 is about 304.0651154664.

The spelling of 28112521 in words is "twenty-eight million, one hundred twelve thousand, five hundred twenty-one".