28380121 has 16 divisors (see below), whose sum is σ = 35988480. Its totient is φ = 21736080.

The previous prime is 28380113. The next prime is 28380139. The reversal of 28380121 is 12108382.

It is a cyclic number.

It is not a de Polignac number, because 28380121 - 2³ = 28380113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28380161) 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 15 ways as a sum of consecutive naturals, for example, 1420 + ... + 7666.

It is an arithmetic number, because the mean of its divisors is an integer number (2249280).

Almost surely, 2^28380121 is an apocalyptic number.

It is an amenable number.

28380121 is a deficient number, since it is larger than the sum of its proper divisors (7608359).

28380121 is a wasteful number, since it uses less digits than its factorization.

28380121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6324.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 28380121 is about 5327.2995973570. The cubic root of 28380121 is about 305.0268577979.

The spelling of 28380121 in words is "twenty-eight million, three hundred eighty thousand, one hundred twenty-one".