28055530 has 16 divisors (see below), whose sum is σ = 50720904. Its totient is φ = 11173120.

The previous prime is 28055483. The next prime is 28055539. The reversal of 28055530 is 3555082.

It can be written as a sum of positive squares in 4 ways, for example, as 20277009 + 7778521 = 4503^2 + 2789^2 .

It is a super-2 number, since 2×28055530² = 1574225527161800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28055539) 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, 3691 + ... + 8350.

Almost surely, 2^28055530 is an apocalyptic number.

28055530 is a deficient number, since it is larger than the sum of its proper divisors (22665374).

28055530 is a wasteful number, since it uses less digits than its factorization.

28055530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12281.

The product of its (nonzero) digits is 6000, while the sum is 28.

The square root of 28055530 is about 5296.7471149754. The cubic root of 28055530 is about 303.8595048509.

The spelling of 28055530 in words is "twenty-eight million, fifty-five thousand, five hundred thirty".