28528251 has 12 divisors (see below), whose sum is σ = 38994936. Its totient is φ = 18551680.

The previous prime is 28528231. The next prime is 28528259. The reversal of 28528251 is 15282582.

It is not a de Polignac number, because 28528251 - 2¹¹ = 28526203 is a prime.

It is a super-2 number, since 2×28528251² = 1627722210238002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28528259) 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, 2215 + ... + 7871.

It is an arithmetic number, because the mean of its divisors is an integer number (3249578).

Almost surely, 2^28528251 is an apocalyptic number.

28528251 is a deficient number, since it is larger than the sum of its proper divisors (10466685).

28528251 is an equidigital number, since it uses as much as digits as its factorization.

28528251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5742 (or 5701 counting only the distinct ones).

The product of its digits is 12800, while the sum is 33.

The square root of 28528251 is about 5341.1844192089. The cubic root of 28528251 is about 305.5566328900.

The spelling of 28528251 in words is "twenty-eight million, five hundred twenty-eight thousand, two hundred fifty-one".