28751121 has 12 divisors (see below), whose sum is σ = 47462272. Its totient is φ = 16429176.

The previous prime is 28751119. The next prime is 28751141. The reversal of 28751121 is 12115782.

It is not a de Polignac number, because 28751121 - 2¹ = 28751119 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28751141) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 228121 + ... + 228246.

Almost surely, 2^28751121 is an apocalyptic number.

28751121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28751121 is a deficient number, since it is larger than the sum of its proper divisors (18711151).

28751121 is a wasteful number, since it uses less digits than its factorization.

28751121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 456380 (or 456377 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 28751121 is about 5362.0071801519. The cubic root of 28751121 is about 306.3502653234.

The spelling of 28751121 in words is "twenty-eight million, seven hundred fifty-one thousand, one hundred twenty-one".