28991056 has 20 divisors (see below), whose sum is σ = 56267604. Its totient is φ = 14470400.

The previous prime is 28991041. The next prime is 28991071. The reversal of 28991056 is 65019982.

It is an interprime number because it is at equal distance from previous prime (28991041) and next prime (28991071).

It can be written as a sum of positive squares in 2 ways, for example, as 46656 + 28944400 = 216^2 + 5380^2 .

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 3 ways as a sum of consecutive naturals, for example, 10986 + ... + 13366.

Almost surely, 2^28991056 is an apocalyptic number.

It is an amenable number.

28991056 is a deficient number, since it is larger than the sum of its proper divisors (27276548).

28991056 is a wasteful number, since it uses less digits than its factorization.

28991056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3150 (or 3144 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 28991056 is about 5384.3343135433. The cubic root of 28991056 is about 307.2000944914.

The spelling of 28991056 in words is "twenty-eight million, nine hundred ninety-one thousand, fifty-six".