28775121 has 8 divisors (see below), whose sum is σ = 38445120. Its totient is φ = 19144272.

The previous prime is 28775113. The next prime is 28775129. The reversal of 28775121 is 12157782.

28775121 = T₅₄ + T₅₅ + ... + T₅₅₆.

It is an interprime number because it is at equal distance from previous prime (28775113) and next prime (28775129).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28775121 - 2³ = 28775113 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28775129) 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 7 ways as a sum of consecutive naturals, for example, 8026 + ... + 11043.

It is an arithmetic number, because the mean of its divisors is an integer number (4805640).

Almost surely, 2^28775121 is an apocalyptic number.

It is an amenable number.

28775121 is a deficient number, since it is larger than the sum of its proper divisors (9669999).

28775121 is a wasteful number, since it uses less digits than its factorization.

28775121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19575.

The product of its digits is 7840, while the sum is 33.

The square root of 28775121 is about 5364.2446812203. The cubic root of 28775121 is about 306.4354835833.

The spelling of 28775121 in words is "twenty-eight million, seven hundred seventy-five thousand, one hundred twenty-one".