28921149 has 18 divisors (see below), whose sum is σ = 43276506. Its totient is φ = 18611040.

The previous prime is 28921147. The next prime is 28921159. The reversal of 28921149 is 94112982.

It can be written as a sum of positive squares in 3 ways, for example, as 10517049 + 18404100 = 3243^2 + 4290^2 .

It is not a de Polignac number, because 28921149 - 2¹ = 28921147 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28921141) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5659 + ... + 9479.

Almost surely, 2^28921149 is an apocalyptic number.

28921149 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28921149 is a deficient number, since it is larger than the sum of its proper divisors (14355357).

28921149 is a wasteful number, since it uses less digits than its factorization.

28921149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3885 (or 3853 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 28921149 is about 5377.8386922629. The cubic root of 28921149 is about 306.9529754993.

The spelling of 28921149 in words is "twenty-eight million, nine hundred twenty-one thousand, one hundred forty-nine".