28840251 has 16 divisors (see below), whose sum is σ = 42640128. Its totient is φ = 17191200.

The previous prime is 28840249. The next prime is 28840277. The reversal of 28840251 is 15204882.

It is not a de Polignac number, because 28840251 - 2¹ = 28840249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28840241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5151 + ... + 9176.

It is an arithmetic number, because the mean of its divisors is an integer number (2665008).

Almost surely, 2^28840251 is an apocalyptic number.

28840251 is a deficient number, since it is larger than the sum of its proper divisors (13799877).

28840251 is a wasteful number, since it uses less digits than its factorization.

28840251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14402.

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 28840251 is about 5370.3120021094. The cubic root of 28840251 is about 306.6665061173. Note that the first 3 decimals are identical.

The spelling of 28840251 in words is "twenty-eight million, eight hundred forty thousand, two hundred fifty-one".