28111985 has 16 divisors (see below), whose sum is σ = 37221120. Its totient is φ = 20211840.

The previous prime is 28111973. The next prime is 28111987. The reversal of 28111985 is 58911182.

It is not a de Polignac number, because 28111985 - 2¹⁰ = 28110961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28111987) 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, 2024 + ... + 7766.

It is an arithmetic number, because the mean of its divisors is an integer number (2326320).

Almost surely, 2^28111985 is an apocalyptic number.

It is an amenable number.

28111985 is a deficient number, since it is larger than the sum of its proper divisors (9109135).

28111985 is a wasteful number, since it uses less digits than its factorization.

28111985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5848.

The product of its digits is 5760, while the sum is 35.

The square root of 28111985 is about 5302.0736509407. The cubic root of 28111985 is about 304.0631829949.

The spelling of 28111985 in words is "twenty-eight million, one hundred eleven thousand, nine hundred eighty-five".