28055657 has 16 divisors (see below), whose sum is σ = 33196800. Its totient is φ = 23208768.

The previous prime is 28055641. The next prime is 28055659. The reversal of 28055657 is 75655082.

It is not a de Polignac number, because 28055657 - 2⁴ = 28055641 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28055657.

It is not an unprimeable number, because it can be changed into a prime (28055659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38228 + ... + 38954.

It is an arithmetic number, because the mean of its divisors is an integer number (2074800).

Almost surely, 2^28055657 is an apocalyptic number.

It is an amenable number.

28055657 is a deficient number, since it is larger than the sum of its proper divisors (5141143).

28055657 is a wasteful number, since it uses less digits than its factorization.

28055657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 920.

The product of its (nonzero) digits is 84000, while the sum is 38.

The square root of 28055657 is about 5296.7591034518. The cubic root of 28055657 is about 303.8599633476.

The spelling of 28055657 in words is "twenty-eight million, fifty-five thousand, six hundred fifty-seven".