28081251 has 24 divisors (see below), whose sum is σ = 45779760. Its totient is φ = 16430400.

The previous prime is 28081243. The next prime is 28081253. The reversal of 28081251 is 15218082.

It is not a de Polignac number, because 28081251 - 2³ = 28081243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28081253) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2020 + ... + 7761.

It is an arithmetic number, because the mean of its divisors is an integer number (1907490).

Almost surely, 2^28081251 is an apocalyptic number.

28081251 is a deficient number, since it is larger than the sum of its proper divisors (17698509).

28081251 is a wasteful number, since it uses less digits than its factorization.

28081251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9827 (or 9824 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 28081251 is about 5299.1745583628. The cubic root of 28081251 is about 303.9523348341.

The spelling of 28081251 in words is "twenty-eight million, eighty-one thousand, two hundred fifty-one".