28578121 has 16 divisors (see below), whose sum is σ = 35038080. Its totient is φ = 22936320.

The previous prime is 28578103. The next prime is 28578127. The reversal of 28578121 is 12187582.

It is not a de Polignac number, because 28578121 - 2⁹ = 28577609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28578127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1056 + ... + 7633.

It is an arithmetic number, because the mean of its divisors is an integer number (2189880).

Almost surely, 2^28578121 is an apocalyptic number.

It is an amenable number.

28578121 is a deficient number, since it is larger than the sum of its proper divisors (6459959).

28578121 is a wasteful number, since it uses less digits than its factorization.

28578121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8736.

The product of its digits is 8960, while the sum is 34.

The square root of 28578121 is about 5345.8508209639. The cubic root of 28578121 is about 305.7345762521.

The spelling of 28578121 in words is "twenty-eight million, five hundred seventy-eight thousand, one hundred twenty-one".