28211256 has 24 divisors (see below), whose sum is σ = 76405680. Its totient is φ = 9403728.

The previous prime is 28211237. The next prime is 28211291. The reversal of 28211256 is 65211282.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 195840 + ... + 195983.

It is an arithmetic number, because the mean of its divisors is an integer number (3183570).

Almost surely, 2^28211256 is an apocalyptic number.

It is an amenable number.

28211256 is an abundant number, since it is smaller than the sum of its proper divisors (48194424).

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

28211256 is a wasteful number, since it uses less digits than its factorization.

28211256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391835 (or 391828 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 28211256 is about 5311.4269269190. The cubic root of 28211256 is about 304.4206722262.

The spelling of 28211256 in words is "twenty-eight million, two hundred eleven thousand, two hundred fifty-six".