28255990 has 32 divisors (see below), whose sum is σ = 58705920. Its totient is φ = 9591264.

The previous prime is 28255979. The next prime is 28255991. The reversal of 28255990 is 9955282.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28255991) 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, 5251 + ... + 9169.

It is an arithmetic number, because the mean of its divisors is an integer number (1834560).

Almost surely, 2^28255990 is an apocalyptic number.

28255990 is an abundant number, since it is smaller than the sum of its proper divisors (30449930).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28255990 is a wasteful number, since it uses less digits than its factorization.

28255990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4036.

The product of its (nonzero) digits is 64800, while the sum is 40.

The square root of 28255990 is about 5315.6363683006. The cubic root of 28255990 is about 304.5814917561.

The spelling of 28255990 in words is "twenty-eight million, two hundred fifty-five thousand, nine hundred ninety".